What Does Crowding Out Even Mean?

Paul Krugman is taking some guff for this column where he argues that the US economy is now at potential, or full employment, so any shift in the federal budget toward deficit will just crowd out private demand.

Whether higher federal spending (or lower taxes) could, in present conditions, lead to higher output is obviously a factual question, on which people may read the evidence in different ways. As it happens, I don’t agree that current output is close to the limits of current productive capacity. But that’s not what I want to write about right now. Instead I want to ask: What concretely would crowding out even mean right now?

Below, I run through six possible meanings of crowding out, and then ask if any of them gives us a reason, even in principle, to worry about over-expansionary policy today. (Another possibility, suggested by Jared Bernstein, is that while we don’t need to worry about supply constraints for the economy as a whole, tax cuts could crowd out useful spending due to some unspecified financial constraint on the federal government. I don’t address that here.) Needless to say, doubts about the economic case for crowding-out are in no way an argument for the specific deficit-boosting policies favored by the new administration.

The most straightforward crowding-out story starts from a fixed supply of private savings. These savings can either be lent to the government, or to business. The more the former takes, the less is left for the latter. But as Keynes pointed out long ago, this simple loanable-funds story assumes what it sets out to prove. The total quantity of saving is fixed only if total income is fixed. If higher government spending can in fact raise total income, it will raise total saving as well. We can only tell a story about government and business competing for a given pool of saving if we have already decided for some other reason that GDP can’t change.

The more sophisticated version, embodied in the textbook ISLM model, postulates a fixed supply of money, rather than saving. [1] In Hicks’ formulation, money is used both for transactions and as the maximally liquid store of wealth. The higher is output, the more money is needed for transactions, and the less is available to be held as wealth. By the familiar logic of supply and demand, this means that wealthholders must be paid more to part with their remaining stock of money. The price wealthholders receive to give up their money is interest; so as GDP rises, so does the interest rate.

Unlike the loanable funds story with fixed saving, this second story does give a logically coherent account of crowding out. In a world of commodity money, if such ever was, it might even be literally true. But in a world of bank-created credit money, it’s at best a metaphor. Is it a useful metaphor? That would require two things. First, that the interest rate (whichever one we are interested in) is set by the financial system. And second, that the process by which this happens causes rates to systematically rise with demand. The first premise is immediately rejected by the textbooks, which tell us that “the central bank sets the interest rate.” But we needn’t take this at face value. There are many interest rates, not just one, and the spreads between them vary quite a bit; logically it is possible that strong demand could lead to wider spreads, as banks stretch must their liquidity further to make more loans. But in reality, the opposite seems more likely. Government debt is a source of liquidity for private banks, not a use of it; lending more to the government makes it easier, not harder, for them to also lend more to private borrowers. Also, a booming economy is one in which business borrowers are more profitable; marginal borrowers look safer and are likely to get better terms. And rising inflation, obviously, reduces the real value of outstanding debt; however annoying this is to bankers, rationally it makes them more willing to lend more to their now less-indebted clients. Wicksell, the semi-acknowledged father of modern central banking theory, built his big book around the premise that in a credit-money system, inflation would give private banks no reason to raise interest rates.

And in fact this is what we see. Interest rate spreads are narrow in booms; they widen in crises and remain wide in downturns.

So crowding out mark two, the ISLM version, requires us to accept both that central banks cannot control the economically relevant interest rates, and that private banks systematically raise interest rates when times are good. Again, in a strict gold standard world there might something to this — banks have to raise rates, their gold reserves are running low — but if we ever lived in that world it was 150 or 200 years ago or more.

A more natural interpretation of the claim that the economy is at potential, is that any further increase in demand would just  lead to inflation. This is the version of crowding out in better textbooks, and also the version used by MMT folks. On a certain level, it’s obviously correct. Suppose the amount of money-spending in an economy increases. Then either the quantity of goods and services increases, or their prices do. There is no third option: The total percent increase in money spending, must equal the sum of the percent increase in “real” output and the percent increase in average prices. But how does the balance between higher output and higher prices play out in real life? One possibility is that potential output is a hard line: each dollar of spending up to there increases real output one for one, and leaves prices unchanged; each dollar of spending above there increases prices one for one and leaves output unchanged. Alternatively, we might imagine a smooth curve where as spending increases, a higher fraction of each marginal dollar translates into higher prices rather than higher output. [2] This is certainly more realistic, but it invites the question of which point exactly on this curve we call “potential”. And it awakens the great bane of postwar macro – an inflation-output tradeoff, where the respective costs and benefits must be assessed politically.

Crowding out mark three, the inflation version, is definitely right in some sense — you can’t produce more concrete use values without limit simply by increasing the quantity of money borrowed by the government (or some other entity). But we have to ask first, positively, when we will see this inflation, and second, normatively, how we value lower inflation vs higher output and income.

In the post-1980s orthodoxy, we as society are never supposed to face these questions. They are settled for us by the central bank. This is the fourth, and probably most politically salient, version of crowding out: higher government spending will cause the central bank to raise interest rates. This is the practical content of the textbook story, and in fact newer textbooks replace the LM curve — where the interest rate is in some sense endogenous — with a straight line at whatever interest rate is chosen by the central bank. In the more sophisticated textbooks, this becomes a central bank reaction function — the central bank’s actions change from being policy choices, to a fundamental law of the economic universe. The master parable for this story is the 1990s, when the Clinton administration came in with big plans for stimulus, only to be slapped down by Alan Greenspan, who warned that any increase in public spending would be offset by a contractionary shift by the federal reserve. But once Clinton made the walk to Canossa and embraced deficit reduction, Greenspan’s fed rewarded him with low rates, substituting private investment in equal measure for the foregone public spending. In the current contest, this means: Any increase in federal borrowing will be offset one for one by a fall in private investment —  because the Fed will raise rates enough to make it happen.

This story is crowding out mark four. It depends, first, on what the central bank reaction function actually is — how confident are we that monetary policy will respond in a direct, predictable way to changes in the federal budget balance or to shifts in demand? (The more attention we pay to how the monetary sausage gets made, the less confident we are likely to be.) And second, on whether the central bank really has the power to reliably offset shifts in fiscal policy. In the textbooks this is taken for granted but there are reasons for doubt. It’s also not clear why the actions of the central bank should be described as crowding out by fiscal policy. The central bank’s policy rule is not a law of nature. Unless there is some other reason to think expansionary policy can’t work, it’s not much of an argument to say the Fed won’t allow it. We end up with something like: “Why can’t we have deficit-financed nice things?” “Because the economy is at potential – any more public spending will just crowd out private spending.” “How will it be crowded out exactly?” “Interest rates will rise.” “Why will they rise?” “Because the federal reserve will tighten.” “Why will they tighten?” “Because the economy is at potential.”

Suppose we take the central bank out of the picture. Suppose we allow supply constraints to bind on their own, instead of being anticipated by the central planners at the Fed. What would happen as demand pushed up against the limits of productive capacity? One answer, again, is rising inflation. But we shouldn’t expect prices to all rise in lockstep. Supply constraints don’t mean that production growth halts at once; rather, bottlenecks develop in specific areas. So we should expect inflation to begin with rising prices for inputs in inelastic supply — land, oil, above all labor. Textbook models typically include a Phillips curve, with low unemployment leading to rising wages, which in turn are passed on to higher prices.

But why should they be passed on completely? It’s easy to imagine reasons why prices don’t respond fully or immediately to changes in wages. In which case, as I’ve discussed before, rising wages will result in an increase in the wage share. Some people will object that such effects can only be temporary. I’m not sure this makes sense — why shouldn’t labor, like anything else, be relatively more expensive in a world where it is relatively more scarce? But even if you think that over the long-term the wage share is entirely set on the supply side, the transition from one “fundamental” wage share to another still has to involve a period of wages  rising faster or slower than productivity growth — which in a Phillips curve world, means a period above or below full employment.

We don’t hear as much about the labor share as the fundamental supply constraint, compared with savings, inflation or interest rates. But it comes right out of the logic of standard models. To get to crowding out mark five, though, we have to take one more step. We have to also postulate that demand in the economy is profit-led — that a distributional shift from profits toward wages reduces desired investment by more than it increases desired consumption. Whether (or which) real economies display wage-led or profit-led demand is a subject of vigorous debate in heterodox macro. But there’s no need to adjudicate that now. Right now I’m just interested in what crowding out could possibly mean.

Demand can affect distribution only if wage increases are not fully passed on to prices. One reason this might happen is that in an open economy, businesses lack pricing power; if they try to pass on increased costs, they’ll lose market share to imports. Follow that logic to its endpoint and there are no supply constraints — any increase in spending that can’t be satisfied by domestic production is met by imports instead. For an ideal small, open economy potential output is no more relevant than the grocery store’s inventory is for an individual household when we go shopping. Instead, like the household, the small open economy faces a budget constraint or a financing constraint — how much it can buy depends on how much it can pay for.

Needless to say, we needn’t go to that extreme to imagine a binding external constraint. It’s quite reasonable to suppose that, thanks to dependence on imported inputs and/or demand for imported consumption goods, output can’t rise without higher imports. And a country may well run out of foreign exchange before it runs out of domestic savings, finance or productive capacity. This is the idea behind multiple gap models in development economics, or balance of payments constrained growth. It also seems like the direction orthodoxy is heading in the eurozone, where competitiveness is bidding to replace inflation as the overriding concern of macro policy.

Crowding out mark six says that any increase in demand from the government sector will absorb scarce foreign exchange that will no longer be available to private sector. How relevant it is depends on how inelastic import demand is, the extent to which the country as a whole faces a binding budget or credit constraint and, what concrete form that constraint faces — what actually happens if international creditors are stiffed, or worry they might be? But the general logic is that higher spending will lead to a higher trade deficit, which at some point can no longer be financed.

So now we have six forms of crowding out:

1. Government competes with business for fixed saving.

2. Government competes with business for scarce liquidity.

3. Increased spending would lead to higher inflation.

4. Increased spending would cause the central bank to raise interest rates.

5. Overfull employment would lead to overfast wage increases.

6. Increased spending would lead to a higher trade deficit.

The next question is: Is there any reason, even in principle, to worry about any of these outcomes in the US today? We can decisively set aside the first, which is logically incoherent, and confidently set aside the second, which doesn’t fit a credit-money economy in which government liabilities are the most liquid asset. But the other four certainly could, in principle, reflect real limits on expansionary policy. The question is: In the US in 2017, are higher inflation, higher interest rates, higher wages or a weaker balance of payments position problems we need to worry about? Are they even problems at all?

First, higher inflation. This is the most natural place to look for the costs of demand pushing up against capacity limits. In some situations you’d want to ask how much inflation, exactly, would come from erring on the side of overexpansion, and how costly that higher inflation would be against the benefits of lower unemployment. But we don’t have to ask that question right now, because inflation is by conventional measures, too low; so higher inflation isn’t a cost of expansionary policy, but an additional benefit. The problem is even worse for Krugman, who has been calling for years now for a higher inflation target, usually 4 percent. You can’t support higher inflation without supporting the concrete action needed to bring it about, namely, a period of aggregate spending in excess of potential. [2] Now you might say that changing the inflation target is the responsibility of the Fed, not the fiscal authorities. But even leaving aside the question of democratic accountability, it’s hard to take this response seriously when we’ve spent the last eight years watching the Fed miss its existing target; setting a new higher target isn’t going to make a difference unless something else happens to raise demand. I just don’t see how you can write “What do we want? Four percent! When do we want it? Now!” and then turn around and object to expansionary fiscal policy on the grounds that it might be inflationary.

OK, but what if the Fed does raise rates in response to any increase in the federal budget deficit, as many observers expect? Again, if you think that more expansionary policy is otherwise desirable, it would seem that your problem here is with the Fed. But set that aside, and assume our choice is between a baseline 2018-2020, and an alternative with the same GDP but with higher budget deficits and higher interest rates. (This is the worst case for crowding out.) Which do we prefer? In the old days, the low-deficit, low-interest world would have been the only respectable choice: Private investment is obviously preferable to whatever government deficits might finance. (And to be fair, in the actual 2018-2020, they will mostly be financing high-end tax cuts.) But as Brad DeLong points out, the calculation is different today. Higher interest rates are now a blessing, not a curse, because they create more running room for the Fed to respond to a downturn. [3] In the second scenario, there will be some help from conventional monetary policy in the next recession, for whatever it’s worth; in the first scenario there will be no help at all. And one thing we’ve surely learned since 2008 is the costs of cyclical downturns are much larger than previously believed. So here again, what is traditionally considered a costs of pushing past supply constraints turns out on closer examination to be a benefit.

Third, the danger of more expansionary policy is that it will lead to a rise in the wage share. You don’t hear this one as much. I’ve suggested elsewhere that something like this may often motivate actual central bank decisions to tighten. Presumably it’s not what someone like Krugman is thinking about. But regardless of what’s in people’s heads, there’s a serious problem here for the crowding-out position. Let’s say that we believe, as both common sense and the textbooks tells us, that the rate of wage growth depends on the level of unemployment. Suppose  we define full employment in the conventional way as the level of unemployment that leads to nominal wage growth just equal to productivity growth plus the central bank’s inflation target. Then by definition, any increase in the wage share requires a period of overfull employment — of unemployment below the full employment level. This holds even if you think the labor share in the long run is entirely technologically determined. A forteori it holds if you think that the wage share is in some sense political, the result of the balance of forces between labor and capital.

Again, I’m simply baffled how someone can believe at the same time that the rising share of capital in national income is a problem, and that there is no space for expansionary policy once full employment is reached. [4] Especially since the unemployment target is missed so often from the other side. If you have periods of excessively high unemployment but no periods of excessively low unemployment, you get a kind of ratchet effect where the labor share can only go down, never up. I think this sort of cognitive dissonance happens because economics training puts aggregate demand in one box and income distribution in another. But this sort of hermetic separation isn’t really sustainable. The wage share can only be higher in the long run if there is some short-run period in which it rises.

Finally, the external constraint. It is probably true that more expansionary fiscal policy will lead to bigger trade deficits. But this only counts as crowding out if those deficits are in some sense unsustainable. Is this the case for the US? There are a lot of complexities here but the key point is that almost all our foreign liabilities (and all of the government’s) are denominated in dollars, and almost all our imports are invoiced in dollars. Personally, I think the world is still more likely to encounter a scarcity of dollar liquidity than a surfeit, so the problem of an external constraint doesn’t even arise. But let’s say I’m wrong and we get the worst-case scenario where the world is no longer willing to hold more dollar liabilities. What happens? Well, the value of the dollar falls. At a stroke, US foreign liabilities decline relative to foreign assets (which are almost all denominated in their home currencies), improving the US net international investment position; and US exports get cheaper for the rest of the world, improving US competitiveness. The problem solves itself.

Imagine a corporation with no liabilities except its stock, and that also paid all its employers and supplies in its own stock and sold its goods for its own stock. How could this business go bankrupt? Any bad news would instantly mean its debts were reduced and its goods became cheaper relative to its competitors’. The US is in a similar position internationally. And if you think that over the medium term the US should be improving its trade balance then, again, this cost of over-expansionary policy looks like a benefit — by driving down the value of the dollar, “irresponsible” policy will set the stage for a more sustainable recovery. The funny thing is that in other contexts Krugman understands this perfectly.

So as far as I can tell, even if we accept that the US economy has reached potential output/full employment, none of the costs for crossing this line are really costs today. Perhaps I’m wrong, perhaps I’m missing something. but it really is incumbent on anyone who argues there’s no space for further expansionary policy to explain what concretely would be the results of overshooting.

In short: When we ask how close the economy is to potential output, full employment or supply constraints, this is not just a factual question. We have to think carefully about what these terms mean, and whether they have the significance we’re used to in today’s conditions. This post has been more about Krugman than I intended, or than he deserves. A very large swathe of established opinion shares the view that the economy is close to potential in some sense, and that this is a serious objection to any policy that raises demand. What I’d like to ask anyone who thinks this is: Do you think higher inflation, a higher “natural” interest rate, a higher wage share or a weaker dollar would be bad things right now? And if not, what exactly is the supply constraint you are worried about?


[1] The LM in ISLM stands for liquidity-money. It’s supposed to be the combination of interest rates and output levels at which the demand for liquidity is satisfied by a given stock of money.

[2] OK, some people might say the Fed could bring about higher inflation just by announcing a different target. But they’re not who I’m arguing with here.

[3] Krugman himself says he’d “be a lot more comfortable … if interest rates were well clear of the ZLB.” How is that supposed to happen unless something else pushes demand above the full employment level at current rates?

[4] It would of course be defensible to say that the downward redistribution from lower unemployment would be outweighed by the upward redistribution from the package of tax cuts and featherbedding that delivered it. But that’s different from saying that a more expansionary stance is wrong in principle.

Rogoff on the Zero Lower Bound

I was at the ASSAs in Chicago this past weekend. [1] One of the most interesting panels I went to was this one, on Advances in Open Economy Macroeconomics. Among other big names, Ken Rogoff was there, as the discussant for a rather strange paper by Pierre-Olivier Gourinchas and Helene Rey.

The Gourinchas and Rey paper, like much of mainstream macro these days, made a big deal of how different everything is at the zero lower bound. Rogoff wasn’t having it. Here’s a rough transcript of what he said:

The obsession with the zero lower bound is encouraging all kinds of wacko ideas. People are saying that at the ZLB, productivity increases are bad (Eggertsson/Krugman/Summers), protectionism is good (Eichngreen), price flexibility is bad, and so on.

But there is an emerging literature that says economists are taking the zero lower bound too literally. In fact, getting negative rates is not that hard. So before you take seriously these, let’s say, very creative ideas, it would be simpler to think about getting rid of the zero bound.

There are lots of ways to do it. I talk about some in my book, but people already understood this back in the 1930s. There was Robert Eisler’s proposal to have banks accept cash deposits at a discount, for instance, which would have effectively created negative rates. If Keynes had read Eisler, he might have gone in a different direction. [2] It’s a very old idea — Kublai Khan did something similar. There will be pushback from the financial sector, of course, who think negative rates will be costly for them, but fundamentally it is not hard to do.

These rather striking comments crystallized something in my mind. What is the big deal about the ZLB? For mainstream macroeconomists, including Gourinchas and Rey in this paper, the reason the ZLB matters is that it prevents the central bank form setting an interest rate low enough to keep output at potential. [3] It’s precisely this that makes inapplicable the conventional analysis of a nonmonetary problem of allocating scarce resources between alternative ends, and requires thinking about other entry points. If the central bank can’t solve the problem of aggregate demand then you have to take it seriously, with all the wacko and/or creative stuff that follows.

In the dominant paradigm, this is a specific technical problem of getting interest rates below zero. Solve that, and we are back in the comfortable Walrasian world. But for those of us on the heterodox side, it is never the case that the central bank can reliably keep output at potential — maybe because market interest rates don’t respond to the policy rate, or because output doesn’t respond to interest rates, or because the central bank is pursuing other objectives, or because there is no well-defined level of “potential” to begin with. (Or, in reality, all four.) So what people like Gourinchas and Rey, or Paul Krugman, present as a special, temporary state of the economy, we see as the general case.

One way of looking at this is that the ZLB is a device to allow economists like Krugman and Gourinchas and Rey — who whatever their scholarly training, are aware of the concrete reality around them — to make Keynesian arguments without forfeiting their academic respectability. You can understand why someone like Rogoff sees that as cheating. We’ve spent decades teaching that the fundamental constraint on the economy is the real endowment of resources and technology; that saving boosts growth; that trade is always win-win; that money and finance matter only in the short run (and the short run is tolerably short). The practical problem of negative policy rates doesn’t let you forget all of that.

Which, if you turn it around, perhaps reflects well on the ZLB crowd. Maybe they want to forget all that? Maybe, you could say, they take the zero lower bound seriously because they don’t take it literally. That is, they treat it as a hard constraint precisely because they are aware that it is only a stand-in for a deeper reality.


[1] The big annual economics conference. It stands for Allied Social Sciences Association — the disciplinary imperialism is right there in the name.

[2] This was an odd thing for Rogoff to say, since of course while Keynes didn’t discuss Eisler as far as I know, he talks at length about the similar proposals for depreciating cash of Silvio Gesell and Major Douglas. Notoriously he says these “brave cranks and heretics” have more to offer than Marx.

[3] Gourinchas and Rey are reality-based enough to say “the policy rate,” not “the interest rate.”


EDIT: Added the seriously-but-not-literally phrasing as suggested by Steve Roth on Twitter.

Can Sanders Do It?

My old professor Jerry Friedman wrote a piece several weeks ago, arguing that a combination of increased public spending and income redistribution (higher minimum wages and other employment regulation favorable to labor) proposed by the Sanders campaign could substantially boost growth and employment during his presidency. As readers of this blog know, this piece has gotten a lot of attention in the past couple of days. Most notably, it inspired a letter from four former CEA chairs strongly rejecting the claim that Sanders proposals could “have huge beneficial impacts on growth rates, income and employment that exceed even the most grandiose predictions by Republicans about the impact of their tax cut proposals.” A number of prominent liberal economists have endorsed the CEA letter or expressed similar doubts.

I want to try to clarify the stakes in this debate. There are three questions, each logically prior to the other.

1. Is it reasonable to think that better macroeconomic policy could deliver substantially higher output and employment?
2. Are the kinds of things proposed by Sanders capable in principle of getting us there?
3. Are the specific numbers in Sanders’ proposals the right ones for such a really-full employment plan?

The second question doesn’t matter until we’ve answered yes to the first one. And the third doesn’t matter until we’ve answered yes to the first two.

The first question is not only logically prior, it also seems to be what the public debate is actually about . The CEA letter, and almost all the other criticism of the Friedman paper I have seen, focuses on whether the outcomes described are plausible at all, not the specific ways they are derived from the Sanders proposals. Almost all the pushback I have seen has been to the effect that 5 percent real GDP growth and 275,000 new jobs per month are not possible results of any conceivable macro policies.

As I’m sure Jerry Friedman would agree, there are plenty of ways his estimates could be improved. But it’s pointless, even disingenuous, to debate the specific numbers before agreeing on the larger questions. I want to focus on the first question here, both because it is the premise of the others and because it is where the debate is currently located.

So: Is it plausible that there could be 5 percent-plus real GDP growth and 300,000 new jobs per month over the eight years of a Sanders presidency? I think it is — or at least, I don’t think there is a good economic argument that it’s not.

I want to make five related points here. First, conventional wisdom in economics is that an exceptionally deep recession should be followed by a period of exceptionally strong growth. Second, the growth in output and employment implied by the paper are more or less what is required to return to the pre-recession trend. Third, discussions of macroeconomic policy in other contexts imply the possibility of growth qualitatively similar to what Jerry describes. Fourth, it is not necessarily the case that the employment Jerry projects would exceed full employment in any meaningful sense. Fifth, if you don’t believe a growth performance at this level is possible, that implies a sharp slowdown in potential output, for which you need a credible story. The last point is probably the most important.
1. It’s not controversial to say that a historically deep recession ought to be followed by a period of historically strong growth. Every macroeconomics textbook teaches that changes in GDP can be split into two components: short-run variation driven by aggregate demand and by monetary and financial factors, and a long-run trend driven by population growth and technological change. While all sorts of things that constrain or inhibit spending can cause temporary dips in production, over time it should converge back to the fundamentals-determined trend. Unless they involve the destruction of real resources — and they don’t — recessions should not have lasting effects. A direct corollary of this textbook view is that the deeper the recession, the stronger should be growth in the following period — otherwise, there’s no way to get back to trend. The people who are saying that Jerry’s growth numbers are impossible on their face are implicitly saying that that we should expect all output losses in recessions to be permanent. This is not orthodox economic theory, at all. Orthodoxy says that the exceptionally deep recession should be followed by a period of exceptionally strong growth — and if it hasn’t been, that suggests some ongoing demand problem which policy can reasonably be expected to solve.
2. Friedman’s growth estimates are just what you need to get output and employment back to trend. This point is well made by Matthew Klein. As Klein puts it, this “supposedly ‘extreme’ and ‘unsupportable’ forecast implies American output will return to its previous trend just as Sanders would be finishing up his second term, in the third quarter of 2024.”

from Matthew Klein, FT Alphaville
from Matthew Klein, FT Alphaville

As Klein and others point out, the level of GDP projected by Jerry for the end of Sanders’ second term is right in line with what the CBO and other establishment forecasters were saying just a few years ago. I just now was looking at the CBO’s forecasts as of January 2013; they were projecting 4-4.5 percent real GDP growth over 2016-2017. This is, of course, exceptionally high by historical standards — Paul Krugman says that Jeb Bush was “rightly mocked” by progressives for suggesting he could deliver growth at that level. But the CBO was making the same prediction and it’s no mystery why — a period of growth well above historical levels is the logical condition of a return of output to trend. By the way, I should emphasize that Friedman’s growth estimates were not derived this way. It’s just a lucky coincidence — if it holds up — that the measures proposed by the Sanders campaign happen to be the right magnitude to close the output gap over eight years.

Similarly, Friedman’s employment numbers (around 277,000 new jobs per month) are indeed way above what we have seen recently. But if you want to get the employment-population ratio back to its 2006 levels by 2024, you need even more than that — about 300,000 new jobs per month, by my calculations. Many respectable economists — including at least one of the CEA signers —  have written that the employment ratio is a better indicator of labor-market conditions than the unemployment rate, and expressed concern about its decline. A few years ago, Brad DeLong had no doubt that more expansionary policy could raise the employment population ratio back to 60.8 percent, if not to the pre-recession level of 63 percent: “we could still put 5.5 million more people to work with appropriate demand-management policies.” To do that by 2024 would imply monthly job growth around 220,000 — less than what Friedman claims for the Sanders proposals, but about double what we are seeing now more than double what the CBO is currently projecting for 2017-2024. It’s just arithmetic: you can’t raise the employment-population ratio without a sustained period of job growth substantially higher than what we are seeing now. So it makes no sense to talk about that as a goal if you think that faster job growth is not a feasible outcome for policy.

It is true, of course, that the aging of the population implies a long-term fall in the employment ratio, all else equal. But let’s put this in perspective. DeLong, for example, suggests that 0.13 points per year is probably an overestimate  of the decline due to demographics. David Rosnick, applying the 2006 employment ratios of various age groups to the population projected for 2026, finds a larger decline due to demographics, on the order of 0.25 points per year. But even that leaves most of the fall in employment unexplained by demographics.  By any standard, there is a lot of room to do better.  But we have to agree that this is something that, in principle, demand  side policy can do.

from David Rosnick

3. In other contexts, it’s taken for granted that more expansionary policy could deliver substantially higher growth. Anyone who says that the zero lower bound is a constraint on monetary policy, or who suggests that the “natural rate of interest” is negative, is saying that output could be substantially higher given more expansionary monetary policy. Presumably, this is true for other forms of expansionary policy as well. (In terms of the model beloved by undergraduate textbooks and New York Times columnists: If the preferred point in ISLM space is to the right of the current one, we should be able to get there by shifting the IS curve just as well as by shifting the LM curve.) Obviously, the transition to that higher level of GDP would involve a period of much higher growth. It would be interesting to ask how fast output would have grown if we’d been able to remove the ZLB constraint in, say, 2010; I suspect the numbers might not look that different from Friedman’s.

Similarly, most participants in this debate agree that the ARRA stimulus of 2009 was effective, with multipliers above 2.0 for at least some categories of spending. Many also think that it should have been bigger. If increased government spending could boost output in 2008, then why couldn’t it today? And if the right answer to “how big?” then was “enough to close the output gap,” why isn’t that the right answer today? Yes, it would be a big number. (Again, it’s a lucky coincidence — if correct — that it happens to be close to what Sanders is proposing.) But so what? If “a trillion has a lot of zeroes”  wasn’t a good argument against an adequate stimulus in 2009, then it isn’t one today.

Or again: If we think that austerity explains a big part of poor growth in European countries, we have to at least consider the the same might be true here. It would be very good luck, to say the least, if years of feuding between the administration and Republican congresses had somehow delivered exactly the right fiscal balance. In general, this discussion has been muddied by the fact that the pragmatic choice to delegate demand management to central banks, has been turned into an axiom in economic theory. From where I’m sitting, the statement “it would be helpful if the central bank set a lower interest rate” is equivalent, for most macroeconomic purposes, with the statement “it would be helpful if the level of public spending were higher.”

4. Friedman’s projections are unreasonable only if you think the US is already at full employment. The unstated but central premise of the critics is that we are at or near full employment, so there is no space for further demand policy. Friedman’s paper says that by the end of a second Sanders term, unemployment would be at 3.8%. Krugman replies:  “It’s possible that we can get unemployment down under 4 percent, but that’s way below any estimates I’ve seen of the level of unemployment consistent with moderate inflation.” Now here we have an interesting question. Whether we are at full employment today depends, first, on how much you think the fall in the employment-population ratio reflects weak demand as opposed to structural or demographic factors — or in other words, to what extent faster job growth would draw nonworkers into the labor market, as opposed to pushing down the unemployment rate. But it also depends on what you think full employment means.

If you believe that any demand-induced acceleration of nominal wage growth will be passed to higher prices, or if you think that price stability should be the sole concern of macro policy, then there will be a hard floor on unemployment, which may not be much lower than where we are today. But if you think some appreciable fraction of faster nominal wage growth would go to an increase in the wage share (or faster productivity growth) rather than to inflation, and if you think some acceleration in inflation is acceptable (or even desirable), then “full employment” becomes a broad region rather than a sharp line. (I wrote a bit about these issues here.) In this case there will even be an argument — made by plenty of mainstream people, including some of the ones criticizing Friedman now  — that a period of “overfull” employment would be desirable to bring the wage share back up from its current historically low levels. To believe that a 3.8% unemployment rate is ruled out by price stability considerations is to claim that faster wage growth cannot raise the wage share, which I don’t think is well supported either theoretically or empirically. (Or that raising the wage share is not desirable.) Also worth recalling: In the debates around the NAIRU in the 1990s, the general conclusion was that the idea of a hard floor to unemployment below which inflation will rise uncontrollably, is not in fact a useful guide for policy.

5. The argument against Friedman’s piece comes down to the claim that the economy is already close to potential. If this is the case then, yes, claims that increased public spending can achieve large gains in output are delusional. I think this is a useful debate to have, but I’m not sure how the CEA chairs would make the case. First, again, many of those criticizing Friedman’s numbers have supported the idea of more expansionary policy in other contexts. Second and more fundamentally, the persistent fall in the employment population ratio and the deviation of output from pre-recession trend seem very hard to explain in “supply” terms. Yes, there are demographic changes, but again, even if you hold the age distribution of the population constant, the employment ratio is still 3 points lower than at the start of the recession. That’s a deficit of 10 million jobs. Closing that gap requires an extended period of above average growth, qualitatively similar to what Friedman describes. If you believe that’s impossible, you have to explain why.

Logically, there are a couple possible answers. Either you argue that the earlier estimates of potential GDP were exaggerated, and we were at overfull employment prior to the recession. If you take this route, you have to be ready to make the case that the country needed substantially slower growth and higher unemployment in the 2000s, despite the noticeable lack of wage growth or rising inflation. Or, you can claim that something happened in 2008-2009 that permanently reduced potential output. So then, what is the negative technological shock that hit the economy in 2008-2009? Is Casey Mulligan right that American businesses have been crippled by the red tape of Obamacare? I don’t think either of those are good options for liberals. Another possibility is to talk about hysteresis and so on — the persistent effects on the laborforce and productivity growth from periods of weak demand. Here you will be on firmer ground — there is plenty of evidence that deep recession inflict lasting harm on workers and businesses. But this kind of reasoning makes Friedman’s numbers more plausible, not less. Because if weak demand can drag potential output down, strong demand can presumably pull it up.

The bottom line is this. Ten years ago, the CBO expected GDP to be $20.5 trillion (correcting for inflation) as of the end of 2015. Today, it is $18.1, trillion, or about 12 percent lower. Similarly, the employment-population ratio fell by 5 points during the recession (from 63.4 to 58.4 percent) and has risen by only one point during the past six years of recovery. Either these facts — unprecedented in the postwar period — reflect a shortfall of effective demand, or they don’t. If they do reflect a lack of demand, then there is no reason the expanded pubic spending and downward redistribution that Sanders proposes cannot close the gap, with a period of high growth while output and employment return to trend. (The fact that such high growth hasn’t been seen in the postwar period is neither here nor there, since there also has been no comparable deviation from trend.) Alternatively, you may think that the shortfall relative to previous growth rates reflects a decline in potential output. But then you need to offer some explanation of why the growth of the economy’s productive capacity slowed so abruptly, and you need to apply this belief consistently. I think it’s more reasonable to believe that the gaps in output and employment reflect a demand shortfall. In which case, the Sanders plan could in principle have the kind of results Friedman describes.


UPDATE: There was a significant error in section 2, which I’ve corrected.

Posts in Three Lines

There is no long run. This short note from the Fed suggests that the failure of output to return to its earlier trend following the Great Recession is not an anomaly; historically, recessions normally involve permanent output losses. This working paper by Lawrence Summers and Lant Pritchett argues that it is very hard to find persistent growth differences between countries. From opposite directions, these results suggest that there is no reason to think that supposedly “slow” variables are more stable than “fast” ones; in other words, there is no economically meaningful long run.

Krugman on the archaeology of “price stability.” Here is Paul Krugman’s talk from the same Roosevelt Institute/AFR/EPI even I spoke at last month. The whole thing is quite good but the most interesting part to me was on the (quite recent) origins of the idea that price stability means 2 percent inflation. From Adam Smith until the 1990s, price stability meant just that, zero inflation; but in the postwar decades it was more or less accepted that that was one objective to trade off against others, rather than the sine qua non of policy success.
Capital is back — or is it? Here’s an interesting figure from Piketty and Zucman’s 2013 paper, showing the long-term evolution of capital and labor shares in the UK and France:
What we see is not a stable or rising capital share, but rather a secular shift in favor of labor income, presumably reflecting the long term growth of political power of working people from the early 19th century, when unions were illegal, labor legislation was unknown and only property owners could vote. What’s funny is that this long-term decline in the power of capital is so clearly visible in Piketty’s data, but so invisible in the discussion of his book.
Orange is the big lie. Like lots of people, I watched the Netflix show Orange Is the New Black and initially enjoyed it, enough to read the memoir on which it’s based. It’s not often you see ideology operation so visibly: The show systematically omits the book’s depictions of abuse and racism among the guards and solidarity among the prisoners, and introduces violence from the prisoners and compassion from the authorities that is not present in the book. For example, both book and show feature an affair between a female prisoner and a male guard, but in the show nothing happens to the prisoner while the guard is fired and prosecuted, while in reality the prisoner was thrown into solitary confinement and there were no consequences for the guard.

The Call Is Coming from Inside the House

Paul Krugman wonders why no one listens to academic economists. Almost all the economists in the IGM Survey agree that the 2009 stimulus bill successfully reduced unemployment and that its benefits outweighed its costs. So why are these questions still controversial?

One answer is that economists don’t listen to themselves. More precisely, liberal economists like Krugman who want the state to take a more active role in managing the economy, continue to teach  an economic theory that has no place for activist policy.

Let me give a concrete example.

One of Krugman’s bugaboos is the persistence of claims that expansionary monetary policy must lead to higher inflation. Even after 5-plus years of ultra-loose policy with no rising inflation in sight, we keep hearing that since so “much money has been created…, there should already be considerable inflation.” (That’s from exhibit A in DeLong’s roundup of inflationphobia.) As an empirical matter, of course, Krugman is right. But where could someone have gotten this idea that an increase in the money supply must always lead to higher inflation? Perhaps from an undergraduate economics class? Very possibly — if that class used Krugman’s textbook.

Here’s what Krugman’s International Economics says about money and inflation:

A permanent increase in the money supply causes a proportional increase in the price level’s long-run value. … we should expect the data to show a clear-cut positive association between money supplies and price levels. If real-world data did not provide strong evidence that money supplies and price levels move together in the long run, the usefulness of the theory of money demand we have developed would be in severe doubt. 


Sharp swings in inflation rates [are] accompanied by swings in growth rates of money supplies… On average, years with higher money growth also tend to be years with higher inflation. In addition, the data points cluster around the 45-degree line, along which money supplies and price levels increase in proportion. … the data confirm the strong long-run link between national money supplies and national price levels predicted by economic theory. 


Although the price levels appear to display short-run stickiness in many countries, a change in the money supply creates immediate demand and cost pressures that eventually lead to future increases in the price level. 


A permanent increase in the level of a country’s money supply ultimately results in a proportional rise in its price level but has no effect on the long-run values of the interest rate or real output. 

This last sentence is simply the claim that money is neutral in the long run, which Krugman continues to affirm on his blog. [1] The “long run” is not precisely defined here, but it is clearly not very long, since we are told that “Even year by year, there is a strong positive relation between average Latin American money supply growth and inflation.”

From the neutrality of money, a natural inference about policy is drawn:

Suppose the Fed wishes to stimulate the economy and therefore carries out an increase in the level of the U.S. money supply. … the U.S. price level is the sole variable changing in the long run along with the nominal exchange rate E$/€. … The only long-run effect of the U.S. money supply increase is to raise all dollar prices.

What is “the money supply”? In the US context, Krugman explicitly identifies it as M1, currency and checkable deposits, which (he says) is determined by the central bank. Since 2008, M1 has more than doubled in the US — an annual rate of increase of 11 percent, compared with an average of 2.5 percent over the preceding decade. Krugman’s textbook states, in  unambiguous terms, that such an acceleration of money growth will lead to a proportionate acceleration of inflation. He can hardly blame the inflation hawks for believing what he himself has taught a generation of economics students.

You might think these claims about money and inflation are unfortunate oversights, or asides from the main argument. They are not. The assumption that prices must eventually change in proportion to the central bank-determined money supply is central to the book’s four chapters on macroeconomic policy in an open economy. The entire discussion in these chapters is in terms of a version of the Dornbusch “overshooting” model. In this model, we assume that

1. Real exchange rates are fixed in the long run by purchasing power parity (PPP).
2. Interest rate differentials between countries are possible only if they are offset by expected changes in the nominal exchange rate.

Expansionary monetary policy means reducing interest rates here relative to the rest of the world. In a world of freely mobile capital, investors will hold our lower-return bonds only if they expect our nominal exchange rate to appreciate in the future. With the long-run real exchange rate pinned down by PPP, the expected future nominal exchange rate depends on expected inflation. So to determine what exchange rate today will make investors willing to holder our lower-interest bonds, we have to know how policy has changed their expectations of the future price level. Unless investors believe that changes in the money supply will translate reliably into changes in the price level, there is no way for monetary policy to operate in this model.

So  these are not throwaway lines. The more thoroughly a student understands the discussion in Krugman’s textbook, the stronger should be their belief that sustained expansionary monetary policy must be inflationary. Because if it is not, Krugman gives you no tools whatsoever to think about policy.

Let me anticipate a couple of objections:

Undergraduate textbooks don’t reflect the current state of economic theory. Sure, this is often true, for better or worse. (IS-LM has existed for decades only in the Hades of undergraduate instruction.) But it’s not much of a defense, is it? If Paul Krugman has been teaching his undergraduates economic theory that produces disastrous results when used as a guide for policy, you would think that would provoke some soul-searching on his part. But as far as I can tell, it hasn’t. But in this case I think the textbook does a good job summarizing the relevant scholarship. The textbook closely follows the model in Dornbusch’s Expectations and Exchange Rate Dynamics, which similarly depends on the assumption that the price level changes proportionately with the money supply. The Dornbusch article is among the most cited in open-economy macroeconomics and international finance, and continues to appear on international finance syllabuses in most top PhD programs.

Everything changes at the zero lower bound. Defending the textbook on the ground that it’s pre-ZLB effectively concedes that what economists were teaching before 2008 has become useless since then. (No wonder people don’t listen.) If orthodox theory as of 2007 has proved to be all wrong in the post-Lehmann world, shouldn’t that at least raise some doubts about whether it was all right pre-Lehmann? But again, that’s irrelevant here, since I am looking at the 9th Edition, published in 2011. And it does talk about the liquidity trap — not, to be sure, in the main chapters on macroeconomic policy, but in a two-page section at the end. The conclusion of that section is that while temporary increases in the money supply will be ineffective at the zero lower bond, a permanent increase will have the same effects as always: “Suppose the central bank can credibly promise to raise the money supply permanently … output will therefore expand, and the currency will depreciate.” (The accompanying diagram shows how the economy returns to full employment.) The only way such a policy might fail is if there is reason to believe that the increase in the money supply will subsequently be reversed. Just to underline the point, the further reading suggested on policy at the zero lower bound is an article by Lars Svennson that calls a permanent expansion in the money supply “the foolproof way” to escape a liquidity trap. There’s no suggestion here that the relationship between monetary policy and inflation is any less reliable at the ZLB; the only difference is that the higher inflation that must inevitably result from monetary expansion is now desirable rather than costly. This might help if Krugman were a market monetarist, and wanted to blame the whole Great Recession and slow recovery on bad policy by the Fed; but (to his credit) he isn’t and doesn’t.

Liberal Keynesian economists made a deal with the devil decades ago, when they conceded the theoretical high ground. Paul Krugman the textbook author says authoritatively that money is neutral in the long run and that a permanent increase in the money supply can only lead to inflation. Why shouldn’t people listen to him, and ignore Paul Krugman the blogger?

[1] That Krugman post also contains the following rather revealing explanation of his approach to textbook writing:

Why do AS-AD? First, you do want a quick introduction to the notion that supply shocks and demand shocks are different … and AS-AD gets you to that notion in a quick and dirty, back of the envelope way. 

Second — and this plays a surprisingly big role in my own pedagogical thinking — we do want, somewhere along the way, to get across the notion of the self-correcting economy, the notion that in the long run, we may all be dead, but that we also have a tendency to return to full employment via price flexibility. Or to put it differently, you do want somehow to make clear the notion (which even fairly Keynesian guys like me share) that money is neutral in the long run. That’s a relatively easy case to make in AS-AD; it raises all kinds of expositional problems if you replace the AD curve with a Taylor rule, which is, as I said, essentially a model of Bernanke’s mind.

This is striking for several reasons. First, Krugman wants students to believe in the “self-correcting economy,” even if this requires teaching them models that do not reflect the way professional economists think. Second, they should think that this self-correction happens through “price flexibility.” In other words, what he wants his students to look at, say, falling wages in Greece, and think that the problem must be that they have not fallen enough. That’s what “a return to full employment via price flexibility” means. Third, and most relevant for this post, this vision of self-correction-by-prices is directly linked to the idea that money is neutral in the long run — in other words, that a sustained increase in the money supply must eventually result in a proportionate increase in prices. What Krugman is saying here, in other words, is that a “surprising big” part of his thinking on pedagogy is how to inculcate the exact errors that drive him crazy in policy settings. But that’s what happens once you accept that your job as an educator is to produce ideological fables.

What Do People Need to Know About International Trade?

On the first day of my trade class, we read Paul Krugman’s article “What Do Undergrads Need to Know About Trade?” In an admirably succinct four pages, it captures all the important things that orthodox trade theory claims to tell us about trade policy. I don’t think orthodox views on trade policy have changed at all in the 20 years since it was written. [1]

So what’s Krugman’s answer? What undergrads need to know, he says, is just what Hume and Ricardo were saying, 200 years ago: If relative costs of production are different in two countries, then total world output, and consumption in each individual country, will always be greater with trade than without, and prices will adjust so that trade is balanced. Free trade is always beneficial for all countries involved.

Krugman’s additions to this Ricardo-Hume catechism are mostly negative — a list of things we don’t need to talk about when talk about trade.

Don’t worry about development. The idea that a country can benefit from changing the sectors or industries it specializes in is, he says “a silly concept.” Yes, we look around the world and see workers in rich countries producing things like airplanes and software, which are worth a lot, and workers in poor countries putting the same effort into producing agricultural goods and textiles, which are worth much less. But

Does this mean the rich country’s high standard of living the result of being in the right sector, or that the poorer country would be richer if it tried to emulate the other’s pattern of specialization? Of course not.

Of course not. This blanket dismissal is rather odd, since the work Krugman won the Nobel for explicitly supports an affirmative answer to both questions. [2] It’s a case of esoteric versus exoteric knowledge, I guess — some truths are not meant for everyone. Or as Krugman delicately puts it, “the innovative stuff is not a priority for undergrads.”

Don’t worry about demand. In debates over policy, “the central issue is employment” in the arguments on both sides. But this is wrong, he says:

The level of employment is a macroeconomic issue, depending in the short run on aggregate demand and depending in the long run on the natural rate of unemployment, with policies like tariffs having little net effect. Trade policy should be debated in terms of its impact on efficiency…

It’s not immediately obvious why the claim that employment depends on aggregate demand is inconsistent with the claim that trade flows have important employment effects. After all, net exports are a component of demand. The implicit assumption is evidently that the central bank (or some other domestic policymaker) is maintaining the level of demand at the full-employment level, and will offset any effects from trade. [3]

Don’t worry about trade deficits, and the financing they require. “The essential things to teach students are still the insights of Ricardo and Hume. That is, trade deficits are self-correcting…”

The whole piece is frankly polemical — it’s clear that the goal is not to educate in the normal sense, but to equip students to take a particular side in public debates. This is not specific to Krugman, of course. If anything, most contemporary textbooks are even worse. [4] One  reason I am using Caves and Frankel in my class is that it has less obnoxious editorializing than other texts I looked at. But less is still a lot.

Enough Krugman-bashing. What’s the alternative? What should people know about international trade? Matias Vernengo has one good alternative list. Here is mine.

There are three frameworks or perspectives in which we can productively think about international trade. The questions we ask in each case will depend on whether we are thinking of trade flows as the adjusting variable, or as reflecting an exogenous change to which some other variable(s) must adjust.

1. Trade flows are part of aggregate expenditure. On the one hand, a good way to predict trade flows is to assume that a fixed fraction of each dollar of spending goes to imported goods. As Joan Robinson and others have stressed, in the short run at least, adjustment of trade balances comes mainly or entirely through income changes. (This is also the perspective developed in Enno Schroeder’s work, which I’ve discussed here before.) On the other hand, if we can’t assume there is some level of full employment or potential output to which to which the economy always returns, then we have to be concerned with trade flows as one factor determining the level of aggregate income. This might be only a short-run phenomenon, as in mainstream Keynesian analysis, or it might be important to economic growth rates over the long run, as in models of balance of payments constrained growth.

2. Trade flows are part of the balance of payments. In a capitalist world economy, there are many different money payments and obligations between countries, of which trade flows are just part. In a world of liquidity constraints, certain configurations of money payments or money commitments are costly, or cannot be achieved at all. That is, a country in the aggregate cannot in general borrow unlimited amounts at “the” world interest rate. The tighter the constraints on a country’s financial position, the more positive a trade balance it must somehow achieve. On the other hand, for a given level of financing constraint, a more positive trade balance allows for more freedom on other dimensions. This interaction between trade flows and financial constraints is central to the balance of payments crises that are such a prominent feature of the modern world economy.

3. Trade flows involve specialization. Thinking now in terms of baskets of goods rather than money flows, the essential thing about international trade is that it allows a country’s consumption and production decisions to be made independently. Given that productive capacities vary more between countries than the mix of consumption goods chosen at a given income and prices, in practice this means that trade allows for specialization in production. If we take productive capacities as given, it follows that trade raises world output and income by allowing countries to specialize according to comparative costs. This is the essential (and genuine) insight of Ricardo. On the other hand, if we think that inherent differences between countries are small and that differences in productive capacity arise mainly through production itself, then international trade will lead to a historically contingent pattern of international specialization in which some positions are more advantageous than others. If causality runs from trade patterns to productive capacities and not just vice versa, then there is a case for including activity trade policy in any development strategy.

The orthodox trade theory has legitimate value and deserves a place in the curriculum. As we’ll discuss in the next post, simple textbook models of the Ricardo-Mill type can be used to tell stories with more interesting political implications than the usual free-trade morality tales. But they are only part of the picture. Much of what matters about trade depends on the fact that it involves flows of money and not just exchanges of goods.

[1] Have Krugman’s views changed since he wrote this? As reflected in his textbooks, no they have not. As reflected in his blog, seems like sometimes yes, sometimes no. Someone should ask him.

[2] For example, one of Krugman’s more widely cited articles is this one, which develops a model in which an innovating region (“the North”) develops new products, which it exports to a non-innovating region (“The South”). In the model,

Higher Northern per capita income depends on the quasi-rents from the Northern monopoly of new products, so the North must continually innovate not only to maintain its relative position but even to maintain its real income in absolute terms. 

This is hard to distinguish from the arguments for industrial policy that Krugman dismisses as silly.

[3] What’s especially odd here is that orthodox theory says that in a world of mobile capital, the only tool the central bank has to maintain full employment is changes in the exchange rate. In standard textbooks (including Krugman’s own), it is impossible for monetary policy to boost employment unless it improves the trade balance.

[4] For example, David Colander’s generally undogmatic intro textbook includes a section titled “If trade is so good, why do so many people oppose it?”The answer turns out to be, they’re just confused.

The Interest Rate, the Interest Rate, and Secular Stagnation

In the previous post, I argued that the term “interest rate” is used to refer to two basically unrelated prices: The exchange rate between similar goods at different periods, and the yield on a credit-market instrument. Why does this distinction matter for secular stagnation?

Because if you think the “natural rate of interest,” in the sense of the credit-market rate that brings aggregate expenditure to a desired level in some real-world economic situation, should be the time-substitution rate that would exist in a model that somehow corresponds to that situation, when the two are in fact unrelated — well then, you are going to end up with a lot of irrelevant and misleading intuitions about what that rate should be.

In general, I do think the secular stagnation conversation is a real step forward. So it’s a bit frustrating, in this context, to see Krugman speculating about the “natural rate” in terms of a Samuelson-consumption loan model, without realizing that the “interest rate” in that model is the intertemporal substitution rate, and has nothing to do with the Wicksellian natural rate. This was the exact confusion introduced by Hayek, which Sraffa tore to pieces in his review, and which Keynes went to great efforts to avoid in General Theory. It would be one thing if Krugman said, “OK, in this case Hayek was right and Keynes was wrong.” But in fact, I am sure, he has no idea that he is just reinventing the anti-Keynesian position in the debates of 75 years ago.

The Wicksellian natural rate is the credit-market rate that, in current conditions, would bring aggregate expenditure to the level desired by whoever is setting monetary policy. Whether or not there is a level of expenditure that we can reliably associate with “full employment” or “potential output” is a question for another day. The important point for now is “in current conditions.” The level of interest-sensitive expenditure that will bring GDP to the level desired by policymakers depends on everything else that affects desired expenditure — the government fiscal position, the distribution of income, trade propensities — and, importantly, the current level of income itself. Once the positive feedback between income and expenditure has been allowed to take hold, it will take a larger change in the interest rate to return the economy to its former position than it would have taken to keep it there in the first place.

There’s no harm in the term “natural rate of interest” if you understand it to mean “the credit market interest rate that policymakers should target to get the economy to the state they think it should be in, from the state it in now.”And in fact, that is how working central bankers do understand it. But if you understand “natural rate” to refer to some fundamental parameter of the economy, you will end up hopelessly confused. It is nonsense to say that “We need more government spending because the natural rate is low,” or “we have high unemployment because the natural rate is low.” If G were bigger, or if unemployment weren’t high, there would be a different natural rate. But when you don’t distinguish between the credit-market rate and time-substitution rate, this confusion is unavoidable.

Keynes understood clearly that it makes no sense to speak of the “natural rate of interest” as a fundamental characteristic of an economy, independent of the current state of aggregate demand:

In my Treatise on Money I defined what purported to be a unique rate of interest, which I called the natural rate of interest — namely, the rate of interest which, in the terminology of my Treatise, preserved equality between the rate of saving (as there defined) and the rate of investment. I believed this to be a development and clarification of Wicksell’s “natural rate of interest”, which was, according to him, the rate which would preserve the stability if some, not quite clearly specified, price-level. 

I had, however, overlooked the fact that in any given society there is, on this definition, a different natural rate of interest for each hypothetical level of employment. And, similarly, for every rate of interest there is a level of employment for which that rate is the “natural” rate, in the sense that the system will be in equilibrium with that rate of interest and that level of employment. Thus it was a mistake to speak of the natural rate of interest or to suggest that the above definition would yield a unique value for the rate of interest irrespective of the level of employment. I had not then understood that, in certain conditions, the system could be in equilibrium with less than full employment. 

I am now no longer of the opinion that the concept of a “natural” rate of interest, which previously seemed to me a most promising idea, has anything very useful or significant to contribute to our analysis. It is merely the rate of interest which will preserve the status quo; and, in general, we have no predominant interest in the status quo as such.

EDIT: In response to Nick Edmonds in comments, I’ve tried to restate the argument of these posts in simpler and hopefully clearer terms:

Step 1 is to recognize that in a model like Samuelson’s, “interest rate” just means any contract that allows you to make a payment today and receive a flow of income in the future. It would be the exact same model, capturing the exact same features of the economy, if we wrote “profit rate” or “house price-to-rent ratio” instead of “interest rate.” Any valid intuition the model gives us, applies to ALL asset yields, not just to the the credit-instrument yields that we call “interest rates” in every day life.

Step 2 is to think about the other factors that enter into real-world asset yields, besides the intertemporal exchange rate Samuelson is interested in — risk, liquidity, carrying costs and depreciation, and expected capital gains. Since all real-world asset yields incorporate at least one of these factors, none correspond exactly to Samuelson’s intertemporal interest rate.

Step 3 is to realize that not only are credit-instrument yields not exactly the Samuelson “interest rate,” they aren’t even approximately it. The great majority of credit market transactions we see in real economies are not exchanges of present income for future income, but exchanges of two different claims on future income. So the intertemporal interest rate enters on both sides and cancels out.

At that point, we have established that the “interest rate” the monetary authority is targeting is not the “interest rate” Samuelson is writing about.

Step 4 is then to ask, what does it mean to say that some particular credit-market interest rate is the “natural” one? That is where the dependence on fiscal policy, income distribution, etc. come in. But those factors are not part of the argument for why the credit-market rate is not even approximately the intertemporal rate.

Secular Stagnation, Progress in Economics

It’s the topic of the moment. Our starting point is this Paul Krugman post, occasioned by this talk by Lawrence Summers.

There are two ways to understand “secular stagnation.” One is that the growth rate of income and output will be slower in the future. The other is that there will be a systematic tendency for aggregate demand to fall short of the economy’s potential output. It’s the second claim that we are interested in.

For Krugman, the decisive fact about secular stagnation is that it implies a need for persistently negative interest rates. That achieved, there is no implication that growth rates or employment need to be lower in the future than in the past. He  is imagining a situation where current levels of employment and growth rates are maintained, but with permanently lower interest rates.

We could also imagine a situation where full employment was maintained by permanently higher public spending, rather than lower interest rates. Or we could imagine a situation where nothing closed the gap and output fell consistently short of potential. What matters is that aggregate expenditure by the private sector tends to fall short of the economy’s potential output, by a growing margin. For reasons I will explain down the road, I think this is a better way of stating the position than a negative “natural rate” of interest.

I think this conversation is a step forward for mainstream macroeconomic thought. There are further steps still to take. In this post I describe what, for me, are the positive elements of this new conversation. In subsequent posts, I will talk about the right way of analyzing these questions more systematically — in terms of a Harrod-type growth model — and  about the wrong way — in terms of the natural rate of interest.

The positive content of “secular stagnation”

1. Output is determined by demand.

The determination of total output by total expenditure is such a familiar part of the macroeconomics curriculum that we forget how subversive it is. It denies the logic of scarcity that is the basis of economic analysis and economic morality. Since Mandeville’s Fable of the Bees, it’s been recognized that if aggregate expenditure determines aggregate income, then, as Krugman says, “vice is virtue and virtue is vice.”

A great deal of the history of macroeconomics over the past 75 years can be thought of as various efforts to expunge, exorcize or neutralize the idea of demand-determined income, or at least to safely quarantine it form the rest of economic theory. One of the most successful quarantine strategies was to recast demand constraints on aggregate output as excess demand for money, or equivalently as the wrong interest rate. What distinguished real economies from the competitive equilibrium of Jevons or Walras was the lack of a reliable aggregate demand “thermostat”. But if a central bank or other authority set that one price or that one quantity correctly, economic questions could again be reduced to allocation of scarce means to alternative ends, via markets. Both Hayek and Friedman explicitly defined the “natural rate” of interest, which monetary policy should maintain, as the rate that would exist in a Walrasian barter economy. In postwar and modern New Keynesian mainstream economics, the natural rate is defined as the market interest rate that produces full employment and stable prices, without (I think) explicit reference to the intertemporal exchange rate that is called the interest rate in models of barter economies. But he equivalence is still there implicitly, and is the source of a great deal of confusion.

I will return to the question of what connection there is, if any, between the interest rates we observe in the world around us, and what a paper like Samuelson 1958 refers to as the “interest rate.” The important thing for present purposes is:

Mainstream economic theory deals with the problems raised when expenditure determines output, by assuming that the monetary authority sets an interest rate such that expenditure just equals potential output. If such a policy is followed successfully, the economy behaves as if it were productive capacity that determined output. Then, specifically Keynesian problems can be ignored by everyone except the monetary-policy technicians. One of the positive things about the secular stagnation conversation, from my point of view, is that it lets Keynes back out of this box.

That said, he is only partway out. Even if it’s acknowledged that setting the right interest rate does not solve the problem of aggregate demand as easily as previously believed, the problem is still framed in terms of the interest rate.

2. Demand normally falls short of potential

Another strategy to limit the subversive impact of Keynes has been to consign him to the sublunary domain of the short run, with the eternal world of long run growth still classical. (It’s a notable — and to me irritating — feature of macroeconomics textbooks that the sections on growth seem to get longer over time, and to move to the front of the book.) But if deviations from full employment are persistent, we can’t assume they cancel out and ignore them when evaluating an economy’s long-run trajectory.

One of the most interesting parts of the Summers talk came when he said, “It is a central pillar of both classical models and Keynesian models, that it is all about fluctuations, fluctuations around a given mean.” (He means New Keynesian models here, not what I would consider the authentic Keynes.) “So what you need to do is have less volatility.” He introduces the idea of secular stagnation explicitly as an alternative to this view that demand matters only for the short run. (And he forthrightly acknowledges that Stanley Fischer, his MIT professor who he is there to praise, taught that demand is strictly a short-run phenomenon.) The real content of secular stagnation, for Summers, is not slower growth itself, but the possibility that the same factors that can cause aggregate expenditure to fall short of the economy’s potential output can matter in the long run as well as in the short run.

Now for Summers and Krugman, there still exists a fundamentals-determined potential growth rate, and historically the level of activity did fluctuate around it in the past. Only in this new era of secular stagnation, do we have to consider the dynamics of an economy where aggregate demand plays a role in long-term growth. From my point of view, it’s less clear that anything has changed in the behavior of the economy. “Secular stagnation” is only acknowledging what has always been true. The notion of potential output was never well defined. Labor supply and technology, the supposed fundamentals, are strongly influenced by the level of capacity utilization. As I’ve discussed before, once you allow for Verdoorn’s Law and hysteresis, it makes no sense to talk about the economy’s “potential growth rate,” even in principle. I hope the conversation may be moving in that direction. Once you’ve acknowledged that the classical allocation-of-scarce-means-to-alternative-ends model of growth doesn’t apply in present circumstances, it’s easier to take the next step and abandon it entirely.

3. Bubbles are functional

One widely-noted claim in the Summers talk is that asset bubbles have been a necessary concomitant of full employment in the US since the 1980s. Before the real estate bubble there was the tech bubble, and before that there was the commercial real estate bubble we remember as the S&L crisis. Without them, the problem of secular stagnation might have posed itself much earlier.

This claim can be understood in several different, but not mutually exclusive, senses. It may be (1) interest rates sufficiently low to produce full employment, are also low enough to provoke a bubble. It may be (2) asset bubbles are an important channel by which monetary policy affects real activity. Or it may be (3) bubbles are a substitute for the required negative interest rates. I am not sure which of these claims Summers intends. All three are plausible, but it is still important to distinguish them. In particular, the first two imply that if interest rates could fall enough to restore full employment, we would have even more bubbles — in the first case, as an unintended side effect of the low rates, in the second, as the channel through which they would work. The third claim implies that if interest rates could fall enough to restore full employment, it would be possible to do more to restrain bubbles.

An important subcase of (1) comes when there is a minimum return that owners of money capital can accept. As Keynes said (in a passage I’m fond of quoting),

The most stable, and the least easily shifted, element in our contemporary economy has been hitherto, and may prove to be in future, the minimum rate of interest acceptable to the generality of wealth-owners.[2] If a tolerable level of employment requires a rate of interest much below the average rates which ruled in the nineteenth century, it is most doubtful whether it can be achieved merely by manipulating the quantity of money.  Cf. the nineteenth-century saying, quoted by Bagehot, that “John Bull can stand many things, but he cannot stand 2 per cent.”

If this is true, then asking owners of money wealth to accept rates of 2 percent, or perhaps much less, will face political resistance. More important for our purposes, it will create an inclination to believe the sales pitch for any asset that offers an acceptable return.

Randy Wray says that Summers is carrying water here for his own reputation and his masters in Finance. The case for bubbles as necessary for full employment justifies his past support for financial deregulation, and helps make the case against any new regulation in the future. That may be true. But I still think he is onto something important. There’s a long-standing criticism of market-based finance that it puts an excessive premium on liquidity and discourages investment in long-lived assets. A systematic overestimate of the returns from fixed assets might be needed to offset the systematic overestimate of the costs of illiquidity.

Another reason I like this part of Summers’ talk is that it moves us toward recognizing the fundamental symmetry between between monetary policy conventionally defined, lender of last resort operations and bank regulations. These are different ways of making the balance sheets of the financial sector more or less liquid. The recent shift from talking about monetary policy setting the money stock to talking about setting interest interest rates was in a certain sense a step toward realism, since there is nothing in modern economies that corresponds to a quantity of money. But it was also a step toward greater abstraction, since it leaves it unclear what is the relationship between the central bank and the banking system that allows the central bank to set the terms of private credit transactions. Self-interested as it may be, Summers call for regulatory forbearance here is an intellectual step forward. It moves us toward thinking of what central banks do neither in terms of money, nor in terms of interest rates, but in terms of liquidity.

Finally, note that in Ben Bernanke’s analysis of how monetary policy affects output, asset prices are an important channel. That is an argument for version (2) of the bubbles claim.

4. High interest rates are not coming back

For Summers and Krugman, the problem is still defined in terms of a negative “natural rate” of interest. (To my mind, this is the biggest flaw in their analysis.) So much of the practical discussion comes down to how you convince or compel wealth owners to hold assets with negative yields. One solution is to move to permanently higher inflation rates. (Krugman, to his credit, recognizes that this option will only be available when or if something else raises aggregate demand enough to push against supply constraints.) I am somewhat skeptical that capitalist enterprises in their current form can function well with significantly higher inflation. The entire complex of budget and invoicing practices assumes that over some short period — a month, a quarter, even a year — prices can be treated as constant. Maybe this is an easy problem to solve, but maybe not. Anyway, it would be an interesting experiment to find out!

More directly relevant is the acknowledgement that interest rates below growth rates may be a permanent feature of the economic environment for the foreseeable future. This has important implications for debt dynamics (both public and private), as we’ve discussed extensively on this blog. I give Krugman credit for saying that with i < g, it is impossible for debt to spiral out of control; a deficit of any level, maintained forever, will only ever cause the debt-GDP ratio to converge to some finite level. (I also give him credit for acknowledging that this is a change in his views.) This has the important practical effect of knocking another leg out from the case for austerity. It’s been a source of great frustration for me to see so many liberal, “Keynesian” economists follow every argument for stimulus with a pious invocation of the need for long-term deficit reduction. If people no longer feel compelled to bow before that shrine, that is progress.

On a more abstract level, the possibility of sub-g or sub-zero interest rates helps break down the quarantining of Keynes discussed above. Mainstream economists engage in a kind of doublethink about the interest rate. In the context of short-run stabilization, it is set by the central bank. But in other contexts, it is set by time preferences and technological tradeoff between current and future goods. I don’t think there was ever any coherent way to reconcile these positions. As I will explain in a following post, the term “interest rate” in these two contexts is being used to refer to two distinct and basically unrelated prices. (This was the upshot of the Sraffa-Hayek debate.) But as long as the interest rate observed in the world (call it the “finance” interest rate) behaved similarly enough to the interest rate in the models (the “time-substitution” interest rate), it was possible to ignore this contradiction without too much embarrassment.

There is no plausible way that the “time substitution” interest rate can be negative. So the secular stagnation conversation is helping reestablish the point — made by Keynes in chapter 17 of the General Theory, but largely forgotten — that the interest rates we observe in the world are something different. And in particular, it is no longer defensible to treat the interest rate as somehow exogenous to discussions about aggregate demand and fiscal policy. When I was debating fiscal policy with John Quiggin, he made the case for treating debt sustainability as a binding constraint by noting that there are long periods historically when interest rates were higher than growth rates. It never occurred to him that it makes no sense to talk about the level of interest rates as an objective fact, independent of the demand conditions that make expansionary fiscal policy desirable. I don’t mean to pick on John — at the time it wasn’t clear to me either.

Finally, on the topic of low interest forever, I liked Krugman’s scorn for the rights of interest-recipients:

How dare anyone suggest that virtuous individuals, people who are prudent and save for the future, face expropriation? How can you suggest steadily eroding their savings either through inflation or through negative interest rates? It’s tyranny!
But in a liquidity trap saving may be a personal virtue, but it’s a social vice. And in an economy facing secular stagnation, this isn’t just a temporary state of affairs, it’s the norm. Assuring people that they can get a positive rate of return on safe assets means promising them something the market doesn’t want to deliver – it’s like farm price supports, except for rentiers.

It’s a nice line, only slightly spoiled by the part about “what the market wants to deliver.” The idea that it is immoral to deprive the owners of money wealth of their accustomed returns is widespread and deeply rooted. I think it lies behind many seemingly positive economic claims. If this conversation develops, I expect we will see more open assertions of the moral entitlement of the rentiers.

Borrowing ≠ Debt

There’s a common shorthand that makes “debt” and “borrowing” interchangeable. The question of why an economic unit had rising debt over some period, is treated as equivalent to the question of why it was borrowing more over that period, or why its expenditure was higher relative to its income. This is a natural way of talking, but it isn’t really correct.

The point of Arjun’s and my paper on debt dynamics was to show that for household debt, borrowing and changes in debt don’t line up well at all. While some periods of rising household leverage — like the housing bubble of the 2000s — were also periods of high household borrowing, only a small part of longer-term changes in household debt can be explained this way. This is because interest, income growth and inflation rates also affect debt-income ratios, and movements in these other variables often swamp any change in household borrowing.
As far as I know, we were the first people to make this argument in a systematic way for household debt. For government debt, it’s a bit better known — but only a bit. People like Willem Buiter or Jamie Galbraith do point out that the fall in US debt after World War II had much more to do with growth and inflation than with large primary surpluses. You can find the argument more fully developed for the US in papers by Hall and Sargent  or Aizenman and Marion, and for a large sample of countries by Abbas et al., which I’ve discussed here before. But while many of the people making it are hardly marginal, the point that government borrowing and government debt are not equivalent, or even always closely linked, hasn’t really made it into the larger conversation. It’s still common to find even very smart people saying things like this:

We didn’t have anything you could call a deficit problem until 1980. We then saw rising debt under Reagan-Bush; falling debt under Clinton; rising under Bush II; and a sharp rise in the aftermath of the financial crisis. This is not a bipartisan problem of runaway deficits! 

Note how the terms “deficits” and “rising debt” are used interchangeably; and though the text mostly says deficits, the chart next to this passage shows the ratio of debt to GDP.
What we have here is a kind of morality tale where responsible policy — keeping government spending in line with revenues — is rewarded with falling debt; while irresponsible policy — deficits! — gets its just desserts in the form of rising debt ratios. It’s a seductive story, in part because it does have an element of truth. But it’s mostly false, and misleading. More precisely, it’s about one quarter true and three quarters false.
Here’s the same graph of federal debt since World War II, showing the annual change in debt ratio (red bars) and the primary deficit (black bars), both measured as a fraction of GDP. (The primary deficit is the difference between spending other than interest payments and revenue; it’s the standard measure of the difference between current expenditure and current revenue.) So what do we see?
It is true that the federal government mostly ran primary surpluses from the end of the war until 1980, and more generally, that periods of surpluses were mostly periods of rising debt, and conversely. So it might seem that using “deficits” and “rising debt” interchangeably, while not strictly correct, doesn’t distort the picture in any major way. But it does! Look more carefully at the 1970s and 1980s — the black bars look very similar, don’t they? In fact, deficits under Reagan were hardy larger than under Ford and Carter —  a cumulative 6.2 percent of GDP over 1982-1986, compared with 5.6 percent of GDP over 1975-1978. Yet the debt-GDP ratio rose by just a single point (from 24 to 25) in the first episode, but by 8 points (from 32 to 40) in the second. Why did debt increase in the 1980s but not in the 1970s? Because in the 1980s the interest rate on federal debt was well above the economy’s growth rate, while in the 1970s, it was well below it. In that precise sense, if debt is a problem it very much is a bipartisan one; Volcker was the appointee of both Carter and Reagan.
Here’s the same data by decades, and for the pre- and post-1980 periods and some politically salient subperiods.  The third column shows the part of debt changes not explained by the primary balance. This corresponds to what Arjun and I call “Fisher dynamics” — the contribution of growth, inflation and interest rates to changes in leverage. [*] The units are percent of GDP.
Totals by Decade
Primary Deficit Change in Debt Residual Debt Change
1950s -8.6 -29.6 -20.9
1960s -7.3 -17.7 -10.4
1970s 2.8 -1.7 -4.6
1980s 3.3 16.0 12.7
1990s -15.9 -7.3 8.6
2000s 23.7 27.9 4.2
Annual averages
Primary Deficit Change in Debt Residual Debt Change
1947-1980 -0.7 -2.0 -1.2
1981-2011 0.1 1.3 1.2
   1981-1992 0.3 1.8 1.5
   1993-2000 -2.7 -1.6 1.1
   2001-2008 -0.1 0.8 0.9
   2009-2011 7.3 8.9 1.6

Here again, we see that while the growth of debt looks very different between the 1970s and 1980s, the behavior of deficits does not. Despite Reagan’s tax cuts and military buildup, the overall relationship between government revenues and expenditures was essentially the same in the two decades. Practically all of the acceleration in debt growth in the 1980s compared with the 1970s is due to higher interest rates and lower inflation.

Over the longer run, it is true that there is a shift from primary surpluses before 1980 to primary deficits afterward. (This is different from our finding for households, where borrowing actually fell after 1980.) But the change in fiscal balances is less than 25 percent the change in debt growth. In other words, the shift toward deficit spending, while real, only accounts for a quarter of the change in the trajectory of the federal debt. This is why I said above that the morality-tale version of the rising debt story is a quarter right and three quarters wrong.

By the way, this is strikingly consistent with the results of the big IMF study on the evolution of government debt ratios around the world. Looking at 60 episodes of large increases in debt-GDP ratios over the 20th century, they find that only about a third of the average increase is accounted for by primary deficits. [2] For episodes of falling debt, the role of primary surpluses is somewhat larger, especially in Europe, but if we focus on the postwar decades specifically then, again, primary surpluses accounted for only a about a third of the average fall. So while the link between government debt and deficits has been a bit weaker in the US than elsewhere, it’s quite weak in general.

So. Why should we care?

Most obviously, you should care if you’re worried about government debt. Now maybe you shouldn’t worry. But if you do think debt is a problem, then you are looking in the wrong place if you think holding down government borrowing is the solution. What matters is holding down i – (g + π) — that is, keeping interest rates low relative to growth and inflation. And while higher growth may not be within reach of policy, higher inflation and lower interest rates certainly are.

Even if you insist on worrying not just about government debt but about government borrowing, it’s important to note that the cumulative deficits of 2009-2011, at 22 percent of GDP, were exactly equal to the cumulative surpluses over the Clinton years, and only slightly smaller than the cumulative primary surpluses over the whole period 1947-1979. So if for whatever reason you want to keep borrowing down, policies to avoid deep recessions are more important than policies to control spending and raise revenue.

More broadly, I keep harping on this because I think the assumption that the path of government debt is the result of government borrowing choices, is symptomatic of a larger failure to think clearly about this stuff. Most practically, the idea that the long-run “sustainability” of the  debt requires efforts to control government borrowing — an idea which goes unquestioned even at the far liberal-Keynesian end of the policy spectrum —  is a serious fetter on proposals for more stimulus in the short run, and is a convenient justification for all sorts of appalling ideas. And in general, I just reject the whole idea of responsibility. It’s ideology in the strict sense — treating the conditions of existence of the dominant class as if they were natural law. Keynes was right to see this tendency to view of all of life through a financial lens — to see saving and accumulating as the highest goals in life, to think we should forego real goods to improve our financial position — as “one of those semicriminal, semi-pathological propensities which one hands over with a shudder to the specialists in mental disease.”

On a methodological level, I see reframing the question of the evolution of debt in terms of the independent contributions of primary deficits, growth, inflation and interest rates as part of a larger effort to think about the economy in historical, dynamic terms, rather than in terms of equilibrium. But we’ll save that thought for another time.

The important point is that, historically, changes in government borrowing have not been the main factor in the evolution of debt-GDP ratios. Acknowledging that fact should be the price of admission to any serious discussion of fiscal policy.

[1] Strictly speaking, debt ratios can change for reasons other than either the primary balance or Fisher dynamics, such as defaults or the effects of exchange rate movements on foreign-currency-denominated debt. But none of these apply to the postwar US.

[2] The picture is a bit different from the US, since adverse exchange-rate movements are quite important in many of these episodes. But it remains true that high deficits are the main factor in only a minority of large increases in debt-GDP ratios.

A Greek Myth

Most days, I’m a big fan of Paul Krugman’s columns.

Unlike his economics, which makes a few too many curtsies to orthodoxy, his political interventions are righteous in tone, right-on in content, and what’s more, strategic — unlike many leftish intellectuals, he clearly cares about being useful — about saying things that are not only true, but that contribute to the concrete political struggle of the moment. He’s so much better than almost of his peers it’s not even funny.

But — well, you knew there had to be a but.

But this time, he’s gotten his economics in his politics. And the results are not pretty.

In today’s column, he rightly dismisses arguments that the root of the Euro crisis is that workers in Greece and the other peripheral countries are lazy, or unproductive, or that those countries have excessive regulation and bloated welfare states. “So how did Greece get into so much trouble?” he asks. His answer:

Blame the euro. Fifteen years ago Greece was no paradise, but it wasn’t in crisis either. Unemployment was high but not catastrophic, and the nation more or less paid its way on world markets, earning enough from exports, tourism, shipping and other sources to more or less pay for its imports. Then Greece joined the euro, and a terrible thing happened: people started believing that it was a safe place to invest. Foreign money poured into Greece, some but not all of it financing government deficits; the economy boomed; inflation rose; and Greece became increasingly uncompetitive.

I’m sorry, but the bolded sentence just is not true. The rest of it is debatable, but that sentence is flat-out false. And it matters.

The analysis behind the “earning enough” claim is found on Krugman’s blog. He writes,

One of the things you keep hearing about Greece is that if it exits the euro one way or another there will be no gains, because Greece basically can’t export — so structural reform is the only way forward. But here’s the thing: if that were true, how did Greece pay its way before the big capital flows starting coming? The truth is that before the euro and the capital flow bubble it created, Greece ran only small current account deficits (the broad definition of the trade balance, including services and factor income)

And he offers this graph from Eurostat:

The numbers in the graph are fine, as far as they go. And there is the first problem: how far they go. Here’s the same graph, but going back to 1980.

Starting the graph ten years earlier gives a different picture — now it seems that the near-balance on current account in 1993 and 1994 wasn’t the normal state before the euro, but an exceptional occurrence in just those two years. And note that that while Greek deficits in the 1980s are small relative to those of the mid-2000s, they are still very far from anything you could reasonably describe as “the country more or less paid its way.” They are, for instance, significantly larger than the contemporaneous US current account deficits that were a central political concern in the 1980s here.

That’s the small problem; there’s a bigger one. Because, what are we looking at? The current account balance. Krugman glosses this as “the broadest measure of the trade balance,” but that’s not correct. (If he taught undergraduate macro, I’m sure he’d mark someone writing that wrong.) It’s broad, yes, but it’s a different concept, covering all international payments other than asset purchases, including some (transfers and income flows) that are not trade by any possible definition. The current account includes, for example, remittances by foreign workers to their home countries. So by Krugman’s logic here, the fact that there are lots of Mexican migrant workers in the US sending money home is a sign that Mexico is able to export successfully to the US, when in the real world it’s precisely a sign that it isn’t.

Most seriously, the current account includes transfer between governments. In the European context these are quite large. To call the subsidies that Greece received under the European Common Agricultural Policy export earnings is obviously absurd. Yet that’s what Krugman is doing.

The following graph shows how big a difference it makes when you call development assistance exports.

The blue line is the current account balance, same as in Krugman’s graph, again extended back to 1980. The red line is the current account balance not counting intergovernmental transfers. And the green line is the current account not counting any transfers. [*] It’s clear from this picture that, contra Krugman, Greece was not earning enough money to pay for its imports before the creation of the euro, or at any time in the past 30 years. If the problem Greece has to solve is getting its foreign exchange payments in line with with its foreign exchange earnings, then the bulk of the problem existed long before Greece joined the euro. The central claim of the column is simply false.

Again, it is true that Greece’s deficits got much bigger in the mid-2000s. I agree with Krugman that this must have ben connected with the large capital flows from northern to peripheral Europe that followed the creation of the euro. It remains an open question, though, how much this was due to an increase in relative costs, and how much due to more rapid income growth. By assuming it was entirely the former, Krugman is implicitly, but characteristically, assuming that except in special circumstances economies can be assumed to be operating at full capacity.

But the key point is that the historical evidence does not support the view that current account imbalances only arise when governments interfere in the natural adjustment of foreign exchange markets. Fixed rates or floating, in the absence of very large flows of intergovernmental aid Greece has never come close to current account balance. According to Krugman, Greece’s

famous lack of competitiveness is a recent development, caused by massive post-euro inflows of capital that raised costs and prices. And that’s the kind of thing that currency devaluations can cure.

The historical evidence is not consistent with this claim. Or if it is, it’s only after you go well beyond normal massaging of the data, to something you’d see on The Client List.

* * *
So why does it matter? What’s at stake? I can’t very well go praising Krugman for writing not only what’s true but what is useful, and then justify a post criticizing him on the grounds of Someone Is Wrong On the Internet. No; but there’s something real at stake here.

The basic issue is, does price adjustment solve everything? Krugman won’t quite come out and say Yes, but clearly it’s what he believes. Is he being deliberately dishonest? No, I’m sure he’s not. But this is how ideology works. He’s committed to the idea that relative costs are the fundamental story when it comes to trade, so when he finds a bit of data that seems to conform to that, he repeats it, without giving five minutes of critical reflection to what it actually means.

The basic issue, again, is the need for structural as opposed to price adjustment. Now if “structural adjustment” means lower wages, then of course Godspeed to Krugman here. I’m against structural whatever in that sense too. But I can’t help feeling that he’s pulling in the wrong direction. Because if external devaluation cures the problem then internal devaluation does too, at least in principle.

The fundamental question remains how important are relative costs. The way I see it, look at what Greece imports, most of it Greece doesn’t produce at all. The textbook expenditure-switching vision implicitly endorsed by Krugman ignores that there are different kinds of goods, or accepts what Paul Davidson calls the axiom of gross substitution, that every good is basically (convexly) interchangeable with every other. Hey Greeks will have fewer computers and no oil, but they’ll spend more time at the beach, and in terms of utility it’s all the same. Except, you know, it’s not.

From where I’m sitting, the only way for Greece to achieve current account balance with income growth comparable to Germany is for Greece to develop new industries. This, not low wages,  is the structural problem. This is the same problem faced by any developing country. And it raises the same problem that Krugman, I’m afraid, has never dealt with: how to you convince or compel the stratum that controls the social surplus to commit to the development of new industries? In the textbook world — which Krugman I’m afraid still occupies — a generic financial system channels savings to the highest-return available investment projects. In the real world, not so much. Figuring out how to get savings to investment is, on the contrary, an immensely challenging institutional problem.

So, first step dealing with it, you should read Gerschenkron. We know, anyway that probably the rich prefer to hold their wealth in liquid form, or overseas, or both. And we know that even if — unlikely — they want to invest in domestic industries, they’ll choose those that are already cost-competitive, when, we know, the whole point of development is to do stuff where you don’t, right now, have comparative advantage. So, again, it’s a problem.

There are solutions to this problem. Banks, the developmental state, even industrial dynasties. But it is a problem, and it needs to be solved. Relative prices are second order. Or so it seems to me.

[*] Unfortunately Eurostat doesn’t seem to have data breaking down nongovernmental transfer payments to Greece. I suspect that the main form of private transfers is remittances from Greek workers elsewhere in Europe, but perhaps not.