(I write a monthly opinion piece for Barron’s. This one was published there in September. My previous pieces are here.)
New data about productivity are some of the best on record in recent years. That’s good news for economic growth. But just as important, it offers support for the unorthodox idea that demand shapes the economy’s productive potential. Taking this idea seriously would require us to rethink much conventional wisdom on macroeconomic policy.
Real output per hour grew 2.6% in 2023, according to the Bureau of Labor Statistics, exceeding the highest rates seen between 2010 and the eve of the pandemic. That said, productivity is one of the most challenging macroeconomic outcomes to measure. It is constructed from three distinct series—nominal output, prices, and employment. Short-term movements often turn out to be noise. It’s an open question whether that high rate will be sustained. But if it is, that will tell us something important about economic growth.
Discussions of productivity growth tend to treat it as the result of unpredictable scientific breakthroughs and new technologies, whose appearance has nothing to do with current economic conditions. This view of technological change as “exogenous,” in the jargon, is entrenched in economics textbooks. And it’s reinforced by the self-mythologizing barons of Silicon Valley, who are only too happy to take credit for economic good news.
The economic conditions that lead companies to actually adopt new technologies get much less attention, as does the fact that much productivity growth comes from people shifting from lower-value to higher-value activities without the need for any new technology at all.
A recent New York Times article is typical. It discusses faster productivity growth almost entirely in terms of the new technologies — AI, Zoom, internet shopping — that might, or might not, be contributing. Not until 40 paragraphs in is there a brief mention of the strong labor market, and the incentives that rising wages create to squeeze more out of each hour of labor.
What if we didn’t treat this as an afterthought? There’s a case to be made that demand is, in fact, a central factor in productivity growth.
The economic historian Gavin Wright has made this case for both the 1990s — our modern benchmarks for productivity success stories — and the 1920s, an earlier period of rapid productivity growth and technological change. Wright considers the adoption of general-purpose technologies: electricity in the ‘20s and computers in the ‘90s. Both had existed for some time but weren’t widely adopted until rising labor costs provided the right incentives. He observes that in both periods strong wage growth started before productivity accelerated.
In the retail sector, for instance, it was in the 1990s that IT applications like electronic monitoring of shelf levels, barcode scanning and electronic payments came into general use. None of these technologies were new at the time; what had changed was the tight market for retail employment that made automation worthwhile.
The idea that demand can have lasting effects on the economy’s productive potential – what economists call hysteresis — has gotten attention in recent years. Discussions of hysteresis tend to focus on labor supply — people dropping out of the labor market when jobs are scarce, and re-entering when conditions improve. The effect of demand on productivity is less often discussed. But it may be even more important.
After the 2007-2009 recession, gross domestic product in the U.S. (and most other rich countries) failed to return to its pre-recession trend. By 2017, a decade after the recession began, real GDP was a full 10% below what prerecession forecasters had expected. There is wide agreement that much, if not all, of this shortfall was the result of the collapse of demand in the recession. Former Treasury Secretary Larry Summers at the time called the decisive role of demand in the slow growth of the 2010s a matter of “elementary signal identification.”
Why did growth fall short? If you look at the CBO’s last economic forecasts before the recession, the agency was predicting 6% growth in employment between 2007 and 2017. And as it turned out, over those ten years, employment grew by exactly 6%. The entire gap between actual GDP and the CBO’s pre-recession forecasts was from slower growth in output per worker. In other words, this shortfall was entirely due to lower productivity.
If you believe that slow growth in the 2010s was largely due to the lingering effects of the recession — and I agree with Summers that the evidence is overwhelming on this point — then what we saw in that decade was weak demand holding back productivity. And if depressed demand can slow down productivity growth, then, logically, we would expect strong demand to speed it up.
A few economists have consistently made the case for this link. Followers of John Maynard Keynes often emphasize this link under the name “Verdoorn’s law.” The law, as Keynesian economist Matias Vernengo puts it in a new article, holds that “technical change is the result, and not the fundamental cause of economic growth.” Steve Fazzari, another Keynesian economist, has explored this idea in severalrecentpapers. But for the most part, mainstream economists have yet to embrace it.
This perspective does occasionally make it into the world of policy debates. In a 2017 report, Josh Bivens of the Economic Policy Institute argued that “low rates of unemployment and rapid wage growth would likely induce faster productivity growth.” Skanda Amarnath and his colleagues at Employ America have made similar arguments. In a 2017 report for the Roosevelt Institute, I discussed a long list of mechanisms linking demand to productivity growth, as well as evidence that this was what explained slower growth since the recession.
If you take these sorts of arguments seriously, the recent acceleration in productivity should not be a surprise. And we don’t need to go looking for some tech startup to thank for it. It’s the natural result of a sustained period of tight labor markets and rising wages.
There are many good reasons for productivity growth to be faster in a tight labor market, as I discussed in the Roosevelt report. Businesses have a stronger incentive to adopt less labor-intensive techniques, and they are more likely to invest when they are running at full capacity. Higher-productivity firms can outbid lower-productivity ones for scarce workers. New firms are easier to start in a boom than in a slump.
When you think about it, it’s strange that concepts like Verdoorn’s law are not part of the economics mainstream. Shouldn’t they be common sense?
Nonetheless, the opposite view underlies much of policymaking, particularly at the Federal Reserve. At his most recent press conference, Fed Chair Jay Powell was asked whether he still thought that wage growth was too high for price stability. Powell confirmed that, indeed, he thought that wage gains were still excessively strong. But, he said, they were gradually moving back to levels “associated — given assumptions about productivity growth — with 2% inflation.”
The Fed’s view that price stability requires limiting workers’ bargaining power is a long-standing problem. But focus now on those assumptions. Taking productivity growth as given, unaffected by policy, risks making the Fed’s pessimism self-confirming. (This is something that Fed economists have worried about in the past.) If the Fed succeeds in getting wages down to the level consistent with the relatively slow productivity growth it expects, that itself may be what stops us from getting the faster productivity growth that the economy is capable of.
The good news is that, as I’ve written here before, the Fed is not all-powerful. The current round of rate hikes has not, so far, done much to cool off the labor market. If that continues to be the case, then we may be in for a period of sustained productivity growth and rising income.
(I am now writing a monthly opinion piece for Barron’s. This one was published there in July.)
To listen to economic policy debates today, you would think the U.S. economy has just one problem: inflation. When Federal Reserve Chairman Jerome Powell was asked at his last press conference if there was a danger in going too far in the fight against inflation, his answer was unequivocal: “The worst mistake we could make is to fail—it’s not an option. We have to restore price stability…because [it’s] everything, it’s the bedrock of the economy. If you don’t have price stability, the economy’s really not going to work.”
Few would dispute that rising prices are a serious problem. But are they everything?
The exclusive focus on inflation acts like a lens on our view of the economy—sharpening our attention on some parts of the picture, but blurring, distorting, and hiding from view many others.
In the wake of the Great Recession, there was a broadening of macroeconomic debates. Economists and policy makers shifted away from textbook truisms toward a more nuanced and realistic view of the economy. Today, this wide-ranging conversation has given way to panic over rising prices. But the realities that prompted those debates have not gone away.
In the clamor over inflation, we’re losing sight of at least four big macroeconomic questions.
First, does the familiar distinction between supply and demand really make sense at the level of the economy as a whole? In the textbooks, supply means the maximum level of production in the economy, labeled “full employment” or “potential output,” while demand means total spending. The two are supposed to be independent—changes in spending don’t affect how much the economy can produce, and vice versa. This is why we are used to thinking of business cycles and growth as two separate problems.
But in the real world, supply often responds to demand—more spending calls forth more investment and draws people into the labor force. This phenomenon, known by the unlovely name “hysteresis,” was clearly visible in the slowdown of labor force and productivity growth after the Great Recession, and their recovery when demand picked up in the years before the pandemic. The key lesson of this experience—in danger of being forgotten in today’s inflation panic—was that downturns are even more costly than we thought, since they not only imply lost output today but reduced capacity in the future.
Hysteresis is usually discussed at the level of the economy as a whole, but it also exists in individual markets and industries. For example, one reason airfares are high today is that airlines, anticipating a more sustained fall in demand for air travel, offered early retirement to thousands of senior pilots in the early stages of the pandemic. Recruiting and training new pilots is a slow process, one airlines will avoid unless it’s clear that strong demand is here to stay. So while conventional wisdom says that rising prices mean that we have too much spending and have to reduce it, in a world with hysteresis a better solution may be to maintain strong demand, so that supply can rise to meet it. In the textbook, we can restore price stability via lower demand with no long-run costs to growth. But are we sure things work so nicely in the real world?
The second big question is about the labor market. Here the textbook view is that there is a unique level of unemployment that allows wages to grow in line with productivity. When unemployment is lower than this “natural rate,” faster wage growth will be passed on to rising prices, until policy makers take action to force unemployment back up. But in the years before the pandemic, it was becoming clear that this picture is too simplistic. Rising wages don’t have to be passed on to higher prices—they may also come at the expense of profits, or spur faster productivity growth. And not all wages are equally responsive to unemployment. Younger, less-educated, and lower-wage workers are more dependent on tight labor markets to find work and get raises, while the incomes of workers with experience and credentials rise more steadily regardless of macroeconomic conditions. This means that—as Powell has acknowledged—macroeconomic policy has unavoidable distributional consequences.
In his classic essay “Political Aspects of Full Employment,” the great Polish economist Michal Kalecki argued that even if it were economically feasible to eliminate unemployment, this would be unsustainable, since employers’ authority in the workplace depends on “the threat of the sack.” Similar arguments have been made by central bank chiefs such as Alan Greenspan, who suggested that low unemployment was sustainable in the 1990s only because workers had been traumatized by the deep recession of the decade before.
Some would argue that it’s unnecessarily wasteful and cruel to maintain labor discipline and price stability by denying millions of people the chance to do useful work—especially given that, prior to the pandemic, unemployment had fallen well below earlier estimates of the “natural rate” with no sign of accelerating inflation. But if we wish to have a permanent full-employment economy, we need to answer a difficult question: How should we manage distributional conflicts between workers and owners (and among workers), and motivate people to work when they have little to fear from losing their job?
A third set of questions concerns globalization. There are widespread fears that renewed Covid lockdowns in China may limit exports to the U.S. and elsewhere. Seen through the inflation lens, this looks like a source of rising prices and a further argument for monetary tightening. But if we take a step back, we might ask whether it is wise to organize the global economy in such a way that lockdowns in China, a war in Ukraine, or even a factory fire in Japan leave people all over the world unable to meet their basic needs. The deepening of trade and financial links across borders is sometimes presented as a fact of nature. But in reality it reflects policy choices that allowed global production of all kinds of goods—from semiconductors to Christmas decorations and latex gloves—to be concentrated in a handful of locations. In some cases, this concentration is motivated by genuine technical advantages of larger-scale production, in others by the pursuit of low wages. But either way, it reflects a prioritization of cost minimization over flexibility and resiliency. Whatever happens with inflation, this is a trade-off that will have to be revisited in coming years, as climate change makes further disruptions in global supply chains all but inevitable.
Then there is climate change. Here, the inflation lens doesn’t just recolor the picture but practically reverses it. Until recently, the conventional wisdom was that a carbon tax was the key policy tool for addressing climate. An Obama-era economist once quipped that the big question on climate was whether a carbon tax was 80% of the solution, or 100%. A carbon tax would increase the prices of energy, which still mainly comes from fossil fuels, and of travel by private car. As it happens, this is exactly what we have seen: Autos and energy have increased much faster than other prices, to the point that these two categories account for a majority of the excess inflation over the past year. In effect, we’ve seen something like a global carbon tax. But far from welcoming the disproportionate rise in the prices of carbon-intensive goods as a silver lining of inflation, both policy makers and the public see it as an urgent problem to be solved.
To be clear, people are not wrong to be unhappy at the rising cost of cars and energy. In the absence of practical alternatives, these high prices inflict real hardship without necessarily doing much to speed the transition from carbon. One reasonable lesson, then, is that a carbon tax high enough to substantially reduce emissions will be politically intolerable. And indeed, before the pandemic, many economists were already shifting away from a carbon-price-focused approach to climate policy toward an investment-centered approach.
Whether via carbon prices or investment, the only way to reduce carbon emissions is to leave fossil fuels in the ground. Yet an increasing swath of the policy conversation is focused on how to encourage more drilling by oil-and-gas companies, not just today but into the indefinite future. As a response to today’s rising energy prices, this is understandable, given the genuine limitations of renewable energy. But how can measures to boost the supply of fossil fuels be consistent with a longer-term program of decarbonization?
None of these questions have easy answers. But the danger of focusing too single-mindedly on inflation is that we may not even try to answer them.
Here’s the very short version of this very long post:
Hysteresis means that a change in GDP today has effects on GDP many years in the future. In principle, this could be because it affects either future aggregate demand or potential output. These two cases aren’t distinguished clearly in the literature, but they have very different implications. The fact that the Great Recession was followed by a period of low inflation, slow wage growth and low interest rates, rather than the opposite, suggests that the persistent-demand form of hysteresis is more important than potential-output hysteresis. The experience of the Great Recession is consistent with perhaps 20 percent of a shock to demand in this period carrying over to demand in future periods. This value in turn lets us estimate how much additional spending would be needed to permanently return GDP to the pre-2007 trend: 50-60 percent of GDP, or $10-12 trillion, spread out over a number of years.
Supply Hysteresis and Demand Hysteresis
The last few years have seen renewed interest in hysteresis – the idea that shifts in demand can have persistent effects on GDP, well beyond the period of the “shock” itself. But it seems to me that the discussion of hysteresis doesn’t distinguish clearly between two quite different forms it could take.
On the one hand, demand could have persistent effects on output because demand influences supply – this seems to be what people usually have in mind. But on the other hand, demand itself might be persistent. In time-series terms, in this second story aggregate spending behaves like a random walk with drift. If we just look at the behavior of GDP, the two stories are equivalent. But in other ways they are quite different.
Let’s say we have a period in which total spending in the economy is sharply reduced for whatever reason. Following this, output is lower than we think it otherwise would have been. Is this because (a) the economy’s productive potential was permanently reduced by the period of reduced spending? Or is it (b) because the level of spending in the economy was permanently reduced? I will call the first case supply hysteresis and the second demand hysteresis.
On the left, supply hysteresis. On the right, demand hysteresis.
It might seem like a semantic distinction, but it’s not. The critical thing to remember is that what matters for much of macroeconomic policy is not the absolute level of output but the output gap — the difference between actual and potential output. If current output is above potential, then we expect to see rising inflation. (Depending on how “potential” is understood, this is more or less definitional.) We also expect to see rising wages and asset prices, shrinking inventories, longer delivery times, and other signs of an economy pushing against supply constraints. If current output is below potential, we expect the opposite — lower inflation or deflation, slower wage growth, markets in general that favor buyers over sellers. So while lower aggregate supply and lower aggregate demand may both translate into lower GDP, in other respects their effects are quite different. As you can see in my scribbles above, the two forms of hysteresis imply opposite output gaps in the period following a deep recession.
Imagine a hypothetical case where there is large fall in public spending for a few years, after which spending returns to its old level. For purposes of this thought experiment, assume there is no change in monetary policy – we’re at the ZLB the whole time, if you like. In the period after the depressed spending ends, will we have (1) lower unemployment and higher inflation than before, as the new income created during the period of high public spending leads to permanently higher demand. Or will we have (2) higher unemployment and lower inflation than if the spending had not occurred, because the period of high spending permanently raised labor force participation and productivity, while demand returns to its old level?
Supply hysteresis implies (1), that a temporary negative demand shock will lead to persistently higher inflation and lower unemployment (because the labor force will be smaller). Demand hysteresis implies (2), that a temporary negative demand shock will lead to permanently lower inflation and higher unemployment. Since the two forms of hysteresis make diametrically opposite predictions in this case, seems important to be clear which one we are imagining. Of course in the real world, could see a combination of both, but they are still logically distinct.
Most people reading this have probably seen a versions of the picture below. On the eve of the pandemic, real per-capita GDP was about 15 percent below where you’d expect it to be based on the pre-2007 trend. (Or based on pre-2007 forecasts, which largely followed the trend.) Let’s say we agree that the deviation is in some large part due to the financial crisis: Are we imagining that output has persistently fallen short of potential, or that potential has fallen below trend? Or again, it might be a combination of both.
In the first case, we would expect monetary policy to be generally looser in the period after a negative demand shock, in the second case tighter. In the first case we’d expect lower inflation in period after shock, in the second case higher.
It seems to me that most of the literature on hysteresis does not really distinguish these cases. This recent IMF paper by Antonio Fatas and coauthors, for example, defines hysteresis as a persistent effect of demand shocks on GDP. This could be either of the two cases. In the text of the paper,they generally assume hysteresis means an effect of demand on supply, and not a persistence of demand itself, but they don’t explicitly spell this out or make an argument for why the latter is not important.
It is clear that the original use of the term hysteresis was understood strictly as what I am calling supply hysteresis. (So perhaps it would be better to reserve the word for that, and make ups new name for the other thing.) If you read the early literature on hysteresis, like these widely-cited Laurence Ballpapers, the focus was on the European experience of the 1980s and 1990s; hysteresis is described as a change in the NAIRU, not as an effect on employment itself. The mechanism is supposed to be a specific labor-market phenomenon: the long term unemployed are no longer really available for work, even if they are counted in the statistics. In other words, sustained unemployment effectively shrinks the labor force, which means that in the absence of policy actions to reduce demand, the period following a deep recession will see faster wage growth and higher inflation than we would have expected.
(This specific form of supply hysteresis implies a persistent rise in unemployment following a downturn, just as demand hysteresis does. The other distinctions above still apply, and other forms of supply hysteresis would not have this implication.)
Set aside for now whether supply-hysteresis was a reasonable description of Europe in the 1980s and 1990s. Certainly it was a welcome alternative to the then-dominant view that Europe needed high unemployment because of over-protective labor market institutions. But whether or not thinking of hysteresis in terms of the NAIRU made sense in that context, it does not make sense for either Europe or the US (or Japan) in the past decade. Everything we’ve seen has been consistent with a negative output gap — with actual output below potential — with a depressed level of demand, not of supply. Wage growth has been unexpectedly weak, not strong; inflation has been below target; and central banks have been making extra efforts to boost spending rather than to rein it in.
Assuming we think that all this is at least partly the result of the 2007-2009 financial crisis — and thinking that is pretty much the price of entry to this conversation — that suggests we should be thinking primarily about demand-hysteresis rather than supply-hysteresis. We should be asking not, or not only, how much and how durably the Great Recession reduced the country’s productive potential, but how how durably it reduced the flow of money through the economy.
It’s weird, once you think about it, how unexplored this possibility is in the literature. It seems to be taken for granted that if demand shocks have a lasting effect on GDP, that must be because they affect aggregate supply. I suspect one reason for this is the assumption — which profoundly shapes modern macroeconomics — that the level of spending in the economy is directly under the control of the central bank. As Peter Dorman observes, it’s a very odd feature of modern macroeconomic modeling that the central bank is inside the model — the reaction of the monetary authorities to, say, rising inflation is treated as a basic fact about the economy, like the degree to which investment responds to changes in the interest rate, rather than as a policy choice. In an intermediate macroeconomics textbook like Carlin and Soskice (a good one as far as they go), students are taught to think about the path of unemployment and inflation as coming out of a “central bank preference function,” which is taken as a fundamental parameter of the economy. Obviously there is no place for demand hysteresis in this framework. To the extent that we think of the actual path of spending in the economy as being chosen by the central bank as part of some kind of optimizing process, past spending in itself will have no effect on current spending.
Be that as it may, it seems hard to deny that in real economies, the level of spending today is strongly influenced by the level of spending in the recent past. This is the whole reason we see booms and depressions as discrete events rather than just random fluctuations, and why they’re described with metaphors of positive-feedback process like “stall speed” or “pump-priming.”1
How Persistent Is Demand?
Let’s say demand is at least somewhat persistent. That brings us to the next question: How persistent? If we were to get extra spending of 1 percent of GDP in one year, how much higher would we now expect demand to be several years later?
We can formalize this question if we write a simple model like:
Zt = Z*t + Xt
Z*t = (1+g) Z*t-1 + a(Zt-1 – Z*t-1)
Here Z is total spending or demand, Z* is the trend, what we might think of as normal or expected demand, g is the normal growth rate, and X is the influence of transitory influences outside of normal growth.
With a = 0, then, we have the familiar story where demand is a trend plus random fluctuations. If we see periods of above- and below-trend demand, that’s because the X influences are themselves extended over time. If a boom year is followed by another boom year, in this story, that’s because whatever forces generated it in the first year are still operating, not because the initial boom itself was persistent.
Alternatively, with a = 1, demand shocks are permanent. Anything that increases spending this year, should be expected to lead to just as much additional spending next year, the year after that, and so on.
Or, of course, a can have any intermediate value.
Think back to 2015, in the debate over the first Sanders’ campaign’s spending plans that was an important starting point for current discussions of hysteresis. The basic mistake Jerry Friedman was accused of making was assuming that changes in demand were persistent — that is, if the multiplier was, say 1.5, that an increase in spending of $500 billion would raise output by $750 billion not only in that year and but in all subsequent years. As his critics correctly pointed out, that is not how conventional multipliers work. In terms of my equations above, he was setting a=1, while the conventional models have a=0.
He didn’t spell this out, and I didn’t think of it that way at the time. I don’t think anyone did. But once you do, it seems to me that while Friedman was wrong in terms of the standard multiplier, he was not wrong about the economy — or at least, no more wrong than the critics. It seems to me that both sides were using unrealistically extreme values. Demand shocks aren’t entirely permanent, but they also aren’t entirely transitory. Arealistic model should have 0 < a < 1.
Demand Persistence and Fiscal Policy
There’s no point in refighting those old battles now. But the same question is very relevant for the future. Most obviously, if demand shocks are persistent to some significant degree, it becomes much more plausible that the economy has been well below potential for the past decade-plus. Which means there is correspondingly greater space for faster growth before we encounter supply constraints in the form of rising inflation.
Both forms of hysteresis should make us less worried about inflation. If we are mainly dealing with supply hysteresis, then rapid growth might well lead to inflation, but it would be a transitory phenomenon as supply catches up to the new higher level of demand.On the other hand, to the extent we are dealing with demand hysteresis, it will take much more growth before we even have to worry about inflation.
Of course, both forms of hysteresis may exist. In which case, both reason for worrying less about inflation would be valid. But we still need to be clear which we are talking about at any given moment.
A slightly trickier point is that the degree of demand persistence is critical for assessing how much spending it will take to get back to the pre-2007 trend.
If the failure to return to the pre-2007 is the lasting effect of the negative demand shock of the Great Recession, it follows thatsufficient spending should be able to reverse the damage and return GDP to its earlier trend. The obvious next question is, how much? The answer really depends on your preferred value for a. In the extreme (but traditional) case of a=0, each year we need enough spending to fill the entire gap, every year, forever. Given a gap of around 12 percent, if we assume a multiplier of 1.5 or so, that implies additional public spending of $1.6 trillion. In the opposite extreme case, where a=1, we just need enough total spending to fill the gap, spread out over however many years. In general, if we want to get close a permanent (as opposed to transitory) output gap of W, we need W/(a μ) total spending, where μ is the conventional multiplier.2
If you project forward the pre-2007 trend in real per-capita GDP to the end of 2019, you are going to get a number that is about 15% higher than the actual figure, implying an output gap on the order of $3.5 trillion. In the absence of demand persistence, that’s the gap that would need to be filled each year. But with persistent demand, a period of elevated public spending would gradually pull private spending up to the old trend, after which it would remain there without further stimulus.
What Does the Great Recession Tell Us about Demand Persistence?
At this point, it might seem that we need to turn to time-series econometrics and try to estimate a value for a, using whatever methods we prefer for such things. And I think that would be a great exercise!
But it seems to me we can actually put some fairly tight limits on a without any econometrics, simple by looking back to the Great Recession. Keep in mind, once we pick an output gap for a starting year, then given the actual path of GDP, each possible value of a implies a corresponding sequence of shocks Xt. (“Shock” here just means anything that causes a deviation of demand from its trend, that is not influenced by demand in the previous period.) In other words, whatever belief we may hold about the persistence of demand, that implies a corresponding belief about the size and duration of the initial fall in demand during the recession. And since we know a fair amount about the causes of the recession, some of these sequences are going to be more plausible than others.
The following figures are an attempt to do this. I start by assuming that the output gap was zero in the fourth quarter of 2004. We can debate this, of course,, but there’s nothing heterodox about this assumption — the CBO says the same thing. Then I assume that in the absence of exogenous disturbances, real GDP per capita would have subsequently grown at 1.4 percent per year. This is the growth rate during the expansion between the Great Recession and the pandemic; it’s a bit slower than the pre-recession trend.3 I then take the gap between this trend and actual GDP in each subsequent quarter and divide it into the part predictable from the previous quarter’s gap, given an assumed value for a, and the part that represents a new disturbance in that period. So each possible value of a, implies a corresponding series of disturbances. Those are what are shown in the figures.
If you’re not used to this kind of reasoning, this is probably a bit confusing. So let me put it a different way. The points in the graphs above show where real GDP would have been relative to the long-term trend if there had been no Great Recession. For example, if you think a = 0, then GDP in 2015 would have been just the same in the absence of the recession, so the values there are just the actual deviation from trend. So you can think of the different figures here as showing the exogenous shocks that would be required under different assumptions about persistence, to explain the actual deviation from trend. They are answering this question: Given your beliefs about how persistent demand is, what must you think GDP would have been in subsequent years in a world where the Great Recession did not take place? (Or maybe better, where the fall in demand form the housing bubble was fully offset by stimulus.)
The first graph, with persistence = 0, is easiest to understand. If there is no carryover of demand shocks from one period to the next, then there must be some factor reducing demand in each later period by the full extent of the gap from trend. If we move on to, say, the persistence=0.1 figure, that is saying that, if you think 10 percent of a demand shock is normally carried over into future periods, that means that there was something happening in 2012 that would have depressed demand by 2 percent relative to the earlier trend, even if there had been no Great Recession.
Because people are used to overcomplicated economics models, I want to stress again. What I am showing you here is what you definitionally believe, if you think that in the absence of the Great Recession, growth in the 2010s would have been at about the same rate it was, just from a higher base, and you think that whatever fraction of a change in spending in one year is carried over to the next year. There are no additional assumptions. I’m just showing what the logical corollary of those beliefs would be for the pattern of demand shocks,
Another important feature of these figures is how large the initial fall in demand is. Logically, if you think demand is very persistent, you must also think the initial shock was smaller. If most of the fall in spending in the first half of 2008, say, was carried over to the second half of 2008, then it takes little additional fall in spending in that period to match the observed path of GDP. Conversely, if you think that very little of a change in demand in one period carries over to the next one then the autonomous fall in demand in 2009 must have been larger.
The question now is, given what we know about the forces impacting demand a decade ago, which of these figures is most plausible? If there had been sufficient stimulus to completely eliminate the fall in demand in 2007-2009, how strong would the headwinds have been a few years late?
Based on what we know about the Great Recession, I think demand persistence in the 0.15 – 0.25 range most plausible. This suggests that a reasonable baseline guess for total spending required to return to the pre-2007 would be around 50 percent of GDP, spread out over a number of years. With an output gap of 15 percent of GDP, a multiplier of 1.5, and demand persistence of 0.2, we have 15 / (1.5 * 0.2) = 50 percent of GDP. This is, obviously, a very rough guess, but if you put me on the spot and asked how much spending over ten years it would take to get GDP permanently back to the pre-2007 trend, $10-12 trillion would be my best guess.
How do we arrive at persistence in the 0.15 – 0.25 range?
On the lower end, we can ask: What are the factors that would have pushed down demand in the mid 2010s, even in the absence of the Great Recession Remember, if we use demand persistence of 0.1, that implies there were factors operating in 2014 that would have reduced demand by 2 percent of GDP, even if the recession had not taken place. What would those be?
I don’t think it makes sense to say housing — housing prices had basically recovered by then. State and local spending is a better candidate — it remained quite depressed and I think it’s hard to see this as a direct effect of the recession. Relative to trend, state and local investment was down about 1 percent of GDP in 2014, while the federal stimulus was basically over. On the other hand, unless we think that monetary policy is totally ineffective, we have to include the stimulative effect of a zero policy rate and QE in our demand shocks. This makes me think that by 2014, the gap between actual GDP and the earlier trend was probably almost all overhang from the recession. And this implies a persistence of at least 0.15. (If you look back at the figures, you’ll see that with persistence=0.15, the implied shock reaches zero in 2014.)
Meanwhile, on the high end, a persistence of 0.5 would mean that the demand shock maxed out at a bit over 3 percent of GDP, and was essentially over by the second half of 2009. This seems implausibly small and implausibly brief. Residential investment fell from 6.5 percent of GDP in 2004 to less than 2.5 percent by 2010. And that is leaving aside housing wealth-driven consumption. Meanwhile, the ARRA stimulus didn’t really come online until the second half of 2009. I don’t believe monetary policy is totally ineffective, but I do think it operates slowly, especially on loosening side. So I find it hard to believe that the autonomous fall in demand in early 2009 was much less than 5 percent of GDP. That implies a demand persistence of no more than 0.25.
Within the 0.15 to 0.25 range, probably the most important variable is your judgement of the effectiveness of monetary policy and the ARRA stimulus. If you think that one or both was very effective, you might think that by mid-2010, they were fully offsetting the fall in demand from the housing bust. This would be consistent withpersistence around 0.25. Conversely, if you’re doubtful about the effectiveness of monetary policy and the ARRA (too little direct spending), you should prefer a value of 0.2 or 0.15.
In any case, it seems to me that the implied shocks with persistence in the 0.15 – 0.25 range look much more plausible than for values outside that range. I don’t believe that the underlying forces that reduced demand in the Great Recession had ceased to operate by the second half of 2009. I also don’t think that they were autonomously reducing demand by as much as 2 points still in early 2014.
You will have your own priors, of course. My fundamental point is that your priors on this stuff have wider implications. I have not seen anyone spell out the question of the persistence of demand in the way I have done here. But the idea is implicit in the way we talk about business cycles. Logically, a demand shortfall in any given period can be described as a mix of forces pulling down spending in that period, and the the ongoing effect of weak demand in earlier periods. And whatever opinion you have about the proportions of each, this can be quantified. What I am doing in this post, in other words, is not proposing a new theory, but trying to make explicit a theory that’s already present in these debates, but not normally spelled out.
Why Is Demand Persistent?
The history of real economies should be enough to convince us that demand can be persistent. Deep downturns — not only in the US after 2007, but in much of Europe, in Japan after 1990, and of course the Great Depression — show clearly that if the level of spending in an economy falls sharply for whatever reason, it is likely to remain low years later, even after the precipitating factor is removed. But why should economies behave this way?
I can think of a couple of reasons.
First, there’s the pure coordination story. Businesses pay wages to workers in order to carry out production. Production is carried out for sale. Sales are generated by spending. And spending depends on incomes, most of which are generated from production. This is the familiar reasoning of the multiplier, where it is used to show how an autonomous change in spending can lead to a larger (or smaller) change in output. The way the multiplier is taught, there is one unique level of output for each level of autonomous demand. But if we formalized the same intuition differently, we could imagine a system with multiple equilibria. Each would have a different level of income, expenditure and production, but in each one people would be making the “right” expenditure choices given their income.
We can make this more concrete in two ways. First, balance sheets. One reason that there is a link from current income to current expenditure is that most economic units are financially constrained to some degree. Even if you knew your lifetime income with great precision, you wouldn’t be able to make your spending decisions on that basis because, in general, you can’t spend the money you will receive in the distant future today.
Now obviously there is some capacity to shift spending around in time, both through credit and through spending down liquid assets. The degree to which this is possible depends on the state of the balance sheet. To the extent a period of depressed demand leaves households and businesses with weaker balance sheets and tighter financial constraints, it will result in lower spending for an extended period. A version of this idea was put forward by Richard Koo as a “balance sheet recession,” in a rather boldly titled book.
Finally there is expectations. There is not, after all, a true lifetime income out there for you to know. All you can do is extrapolate from the past, and from the experiences of other people like you. Businesses similarly must make decisions about how much investment to carry out based on extrapolation from the past – on what other basis could they do it?
A short period of unusually high or low demand may not move expectations much, but a sustained one almost certainly will. A business that has seen demand fall short of what they were counting on is going to make more conservative forecasts for the future. Again, how could they not? With the balance sheet channel, one could plausibly agree that demand shocks will be persistent but not permanent. But with expectations, once they have been adjusted, the resulting behavior will in general make them self-confirming, so there is no reason spending should ever return to its old path.
This, to me, is the critical point. Mainstream economists and policy makers worry a great deal about inflation expectations, and whether they are becoming “unanchored.” But expectations of inflation are not the only ones that can slip their moorings. Households and businesses make decisions based on expectations of future income and sales, and if those expectations turn out to be wrong, they will be adjusted accordingly. And, as with inflation, the outcomes of which people form expectations themselves largely depend on expectations.
This was a point emphasized by Keynes:
It is an essential characteristic of the boom that investments which will in fact yield, say, 2 per cent in conditions of full employment are made in the expectation of a yield of, say, 6 per cent, and are valued accordingly.
When the disillusion comes, this expectation is replaced by a contrary ‘error of pessimism’, with the result that the investments, which would in fact yield 2 per cent in conditions of full employment, are expected to yield less than nothing; and the resulting collapse of new investment then leads to a state of unemployment in which the investments, which would have yielded 2 per cent in conditions of full employment, in fact yield less than nothing. We reach a condition where there is a shortage of houses, but where nevertheless no one can afford to live in the houses that there are.
He continues the thought in terms that are very relevant today:
Thus the remedy for the boom is not a higher rate of interest but a lower rate of interest! For that may enable the so-called boom to last. The right remedy for the trade cycle is not to be found in abolishing booms and thus keeping us permanently in a semi-slump; but in abolishing slumps and thus keeping us permanently in a quasi-boom.
Some people are frustrated about the surrender on the minimum wage, the scaled-back unemployment insurance, the child tax credit that should have been a universal child allowance, the fact that most of the good things phase out over the next year or two.
On the other side are those who see it as a decisive break with neoliberalism. Both the Clinton and Obama administrations entered office with ambitious spending plans, only to abandon or sharply curtail them (respectively), and instead embrace a politics of austerity and deficit reduction. From this point of view, the fact that the Biden administration not only managed to push through an increase in public spending of close to 10 percent of GDP, but did so without any promises of longer-term deficit reduction, suggests a fundamental shift.
Personally, I share this second perspective. I am less surprised by the ways in which the bill was trimmed back, than by the extent that it breaks with the Clinton-Obama model. The fact that people like Lawrence Summers have been ignored in favor of progressives like Heather Boushey and Jared Bernstein, and deficit hawks like the Committee for a Responsible Federal Budget have been left screeching irrelevantly from the sidelines, isn’t just gratifying as spectacle. It suggests a big move in the center of gravity of economic policy debates.
It really does seem that on the big macroeconomic questions, our side is winning.
To be clear, the bill did not pass because some economists out-argued other economists. It was a political outcome that was driven by political conditions and political work. Most obviously, it’s hard to imagine this Biden administration without the two Sanders campaigns that preceded it. (In the president’s speech after signing the bill, Bernie was the first second person credited.) If it’s true, as reported, that Schumer kept expanded unemployment benefits in the bill only by threatening Manchin that the thing would not pass the House without them, then the Squad also deserves a lot of credit.
Still, from my parochial corner, it’s interesting to think about the economic theory implied by the bill. Implicitly, it seems to me, it represents a big break with prevailing orthodoxy.
Over the past generation, macroeconomic policy discussions have been based on a kind of textbook catechism that goes something like this: Over the long run, potential GDP grows at a rate based on supply-side factors — demographics, technological growth, and whatever institutions we think influence investment and labor force participation. Over the short run, there are random events that can cause actual spending to deviate from potential, which will be reflected in a higher or lower rate of inflation. These fluctuations are more or less symmetrical, both in frequency and in cost. The job of the central bank is to adjust interest rates to minimize the size of these deviations. The best short-term measure of how close the economy is to potential is the unemployment rate; at any given moment, there’s a minimum level of unemployment consistent with price stability. Smoothing out these fluctuations has real short run benefits, but no effects on long-term growth. The government budget balance, meanwhile, should not be used to stabilize demand, but rather should be kept at a level that ensures a stable or falling debt ratio; large fiscal deficits may be very costly. Finally, while it may be necessary to stabilize overall spending in the economy, this should be done in a way that minimizes “distortions” of the pattern of economic activity and, in particular, does not reduce the incentive to work.
Policy debates — though not textbooks — have been moving away from this catechism for a while. Jason Furman’s New View of Fiscal Policy is an example I often point to; you can also see it in many statements from Powell and other Fed officials, as I’ve discussed here and here. But these are, obviously, just statements. The size and design of ARPA is a more consequential rejection of this catechism. Without being described as such, it’s a decisive recognition of half a dozen points that those of us on the left side of the macroeconomic debate have been making for years.
1. The official unemployment rate is an unreliable guide to the true degree of labor market slack, all the time and especially in downturns. Most of the movement into and out of employment is from people who are not officially counted as unemployed. To assess labor market slack, we should also look at the employment-population ratio, and also at more direct measures of workers’ bargaining power like quit rates and wage increases. By these measures, the US pre-pandemic was still well short of the late 1990s.More broadly, there is not a well defined labor force, but asmooth gradient of proximity to employment. The short-term unemployed are the closest, followed by the longer-term unemployed, employed people seeking additional work, discouraged workers, workers disfavored by employers due to ethnicity, credentials, etc. Beyond this are people whose claim on the social product is not normally exercised by paid labor – retired people, the disabled, full-time caregivers – but might come to be if labor market conditions were sufficiently favorable.
2. The balance of macroeconomic risks is not symmetrical. We don’t live in an economy that fluctuates around a long-term growth path, but one that periodically falls into recessions or depressions. These downturns are a distinct category of events, not a random “shock” to production or desired spending. Economic activity is a complex coordination problem; there are many ways it can break down or be interrupted that result in a fall inspending, but not really any way it can abruptly accelerate. (There are no “positive shocks” for the same reason that there are lots of poisons but no wonder drugs.) It’s easy to imagine real-world developments that could causes businesses to abruptly cut back their investment plans, but not that would cause them to suddenly and unexpectedly scale them up. In real economies, demand shortfalls are much more frequent, persistent and damaging than is overheating. And to the extent the latter is a problem, it is much easier to interrupt the flow of spending than to restart it.
3. The existence of hysteresis is one important reason that demand shortfalls are much more costly than overshooting. Overheating may have short-term costs in higher inflation, inflated asset prices and a redistribution of income toward relatively scarce factors (e.g. urban land), but it also is associated with a long-term increase in productive capacity — one that may eventually close the inflationary gap on its own. Shortfalls on the other hand lead to a reduction in potential output, and so may become self-perpetuating as potential GDP declines. Hysteresis also means that we cannot count on the economy returning to its long-term trend on its own — big falls in demand may persist indefinitely unless they are offset by some large exogenous boost to demand. Which in turn means that standard estimates of potential output understate the capacity of output to respond to higher spending.
4. A full employment or high pressure economy has benefits that go well beyond the direct benefits of higher incomes and output. Hysteresis is part of this — full employment is a spur to innovation and faster productivity growth. But there are also major implications for the distribution of income. Those who are most disadvantaged in the labor market, are the ones who benefit most from very low unemployment. The World War II experience, and the subsequent evolution of the racial wage gap, suggests that historically, sustained tight labor markets have been the most powerful force for closing the gap between black and white wages.
I’m not sure how much people in the administration and Congress were actually making arguments like these in framing the bill. But even if they weren’t explicitly argued for, some mix of them logically follows from the willingness to pass something so much larger than the conventional estimates of the output gap would imply. Some mix of them also must underly the repeated statements that we can’t do too much, only too little, and from the recognition that the costs of an inadequate stimulus in 2009 were not just lower output for a year or two, butan extended period of slow growth and stagnant wages. When Schumer says that in 2009, “we cut back on the stimulus dramatically and we stayed in recession for five years,” he is espousing a model of hysteresis, even if he doesn’t use the word.
On other points, there’s a more direct link between the debate over the bill and the shift in economic vision it implies.
5. Public debt doesn’t matter. Maybe I missed it, but as far as I can tell, in the push for the Rescue Plan neither the administration nor the Congressional leadership made even a gesture toward deficit reduction, not even a pro forma comment that it might be desirable in principle or in the indefinite long run. The word “deficit” does not seem to have occurred in any official statement from the president since early February — and even then it was in the form of “it’s a mistake to worry about the deficit.” Your guide to being a savvy political insider suggests appropriate “yes, buts” to the Rescue Plan — too much demand will cause inflation, or alternatively that demand will collapse once the spending ends. Nothing about the debt. Things may change, of course, but at the moment it’s astonishing how completely we have won on this one.
6. Work incentives don’t matter. For decades, welfare measures in the US have been carefully tailored to ensure that they did not broaden people’s choices other than wage labor. The commitment to maintaining work incentives was strong enough to justify effectively cutting off all cash assistance to families without anyone in paid employment — which of course includes the poorest.The flat $600 pandemic unemployment insurance was a radical departure from this — reaching everyone who was out of work took priority over ensuring that no one was left better off than they would be with a job. The empirical evidence that this had no effect on employment is informative about income-support programs in general. Obviously $300 is less than $600, but it maintains the priority of broad eligibility. Similarly, by allowing families with no wages to get the full benefit, making the child tax credit full refundable effectively abandons work incentives as a design principle (even if it would be better at that point to just make it a universal child allowance.) As many people have pointed out, this is at least directionally 180 degrees from Clinton-era “welfare reform.”
7.Direct, visible spending is better than indirect spending or spending aimed at altering incentives. For anyone who remembers the debates over the ARRA at the start of the Obama administration, it’s striking how much the Rescue Plan leans into direct, visible payments to households. The plan to allow the child tax credit to be paid out in monthly installments may have some issues (and, again, would certainly work better if it were a flat allowance rather than a tax credit) but what’s interesting here is that it reflects a view that making the payments more salient is a good thing, not a bad thing.
In other areas, the conceptual framework hasn’t moved as far as I would have hoped, though we are making progress:
8. Means testing is costly and imprecise. As Claudia Sahm, Matt Bruenig and others have forcefully argued, there’s a big disconnect between the way means testing is discussed and the way it actually operates. When the merits of income-based spending are talked about in the abstract, it’s assumed that we know every household’s income and can assign spending precisely to different income groups. But when we come to implement it, we find that the main measure of income we use is based on tax records from one to two years earlier; there are many cases where the relevant income concept isn’t obvious; and the need to document income creates substantial costs and uncertainties for beneficiaries. Raising the income thresholds for things like the child tax credit is positive, but the other side of that is that once the threshold gets high enough it’s perverse to means-test at all: In order to exclude a relatively small number of high-income families you risk letting many lower-income families fall through the cracks.
9. Weak demand is an ongoing problem, not just a short-term one. The most serious criticism of the ARPA is, I think, that so many of its provisions are set to phase out at specific dates when they could be permanent (the child tax credit) or linked to economic conditions (the unemployment insurance provisions). This suggests an implicit view that the problems of weak demand and income insecurity are specific to the coronavirus, rather than acute forms of a chronic condition. This isn’t intended as a criticism of those who crafted the bill — it may well be true that a permanent child tax credit couldn’t be passed under current conditions.
Still, the arguments in support of many of the provisions are not specific to the pandemic, and clearly imply that these measures ought to be permanent. If the child tax credit will cut child poverty by half, why would you want to do that for only one year? If a substantial part of the Rescue Plan should on the merits be permanent, that implies a permanently larger flow of public spending. The case needs to be made for this.
10. The public sector has capacities the private sector lacks. While Biden’s ARPA is a big step forward from Obama’s ARRA in a lot of ways, one thing they have in common is a relative lack of direct public provision. The public health measures are an exception, of course, and the aid to state and local governments — a welcome contrast with ARRA — is public spending at one remove, but the great majority of the money is going to boost private spending. That’s not necessarily a bad thing in this specific context, but it does suggest that, unlike the case with public debt, theinstitutional and ideological obstacles to shifting activities from for-profit to public provision are still formidable.
My goal in listing these points isn’t, to be clear, to pass judgement on the bill one way or the other. Substantively, I do think it’s a big victory and a clear sign that elections matter. But my interest in this particular post is to think about what it says about how thinking about economic policy is shifting, and how those shifts might be projected back onto economic theory.
What would a macroeconomics look like that assumed that the economy was normally well short of supply constraints rather than at potential on average, or was agnostic about whether there was a meaningful level of potential output at all? What would it look like if we thought that demand-induced shifts in output are persistent, in both directions? Without the assumption of a supply-determined trend which output always converges to, it’s not clear there’s a meaningful long run at all. Can we have a macroeconomic theory that dispenses with that?
One idea that I find appealing is to think of supply as constraining the rate of growth of output, rather than its level. This would fit with some important observable facts about the world — not just that demand-induced changes in output are persistent, but also that employment tends to grow (and unemployment tends to fall) at a steady rate through expansions, rather than a quick recovery and then a return to long-run trend. The idea that there is a demographically fixed long-run employment-population ratio flies in the face of the major shifts of employment rates within demographic groups. A better story, it seems to me, is that there is a ceiling on the rate that employment can grow — say 1.5 or 2 percent a year — without any special adjustment process; faster growth requires drawing new people into the labor force, which typically requires faster wage growth and also involves various short run frictions. But, once strong growth does generate a larger labor force, there’s no reason for it to revert back to its old trend.
More broadly, thinking of supply constraints in terms of growth rates rather than levels would let us stop thinking about the supply side in terms of an abstract non monetary economy “endowed” with certain productive resources, and start thinking about it in terms of the coordination capabilities of markets. I feel sure this is the right direction to go. But a proper model needs to be worked out before it is ready for the textbooks.
The textbook model of labor markets that we still teach justifies a focus on “flexibility”, where real wages are determined by on productivity and a stronger position for labor can only lead to higher inflation or unemployment. Instead, we need a model where the relative position of labor affects real as well as nominal wages, andin which faster wage growth can be absorbed by faster productivity growth or a higher wage share as plausibly as by higher prices.
Or again, how do we think about public debt and deficits once we abandon the idea that a constant debt-GDP ratio is a hard constraint? One possibility is that we think the deficit matters, but debt does not, just as we now think think that the rate of inflation matters but the absolute price level does not.To earlier generations of economists, the idea that prices could just rise forever without limit, would have seemed insane. But today we find it perfectly reasonable, as long as the rise over any given period is not too great. Perhaps we’ll come to the same view of public debt. To the extent that we do care about the debt ratio, we need to foreground the fact that its growth over time depends as much on interest, inflation and growth rates as it does on new borrowing. For the moment, the fact that interest rates are much lower than growth rates is enough to convince people past concerns were overblown. But to regard that as a permanent rather than contingent solution, we need, at least, to get rid of the idea of a natural rate of interest.
In short, just as a generation of mainstream macroeconomic theory was retconned into an after-the-fact argument for an inflation-targeting central bank, what we need now is textbooks and theories that bring out, systematize and generalize the reasoning that justifies a great expansion of public spending, unconstrained by conventional estimates of potential output, public debt or the need to preserve labor-market incentives. The circumstances of the past year are obviously exceptional, but that doesn’t mean they can’t be made the basis of a general rule. For the past generation, macroeconomic theory has been largely an abstracted parable of the 1970s, when high interest rates (supposedly) saved us from inflation. With luck, perhaps the next generation will learn macroeconomics as a parable of our own time, when big deficits saved us from secular stagnation and the coronavirus.
(EDIT: It’s not sufficiently clear in the original post, but I wrote this as a sort of compendium of arguments one might use in response to claims that the federal debt is a binding constraint on new spending. I’m not saying these are the best or only reasons to reject the idea that federal government cannot borrow more. I’m saying that these are arguments that seem to have some traction in the mainstream policy world, such that you could use them in a newspaper op-ed or conversation with a congress member’s staff. Also, a premise here is that there are urgent needs we want the public sector to spend more on. Apart from the last couple, these are not arguments for more public dbet as an end in itself.)
Why might larger budget deficits be ok?
There are a number of reasons why economists, policymakers and advocates believe that increased public borrowing is not something to be afraid of. As I’ll discuss below, the fundamental factor linking most of these reasons is the idea that the US economy is generally operating below capacity.
When we think about the fiscal balance – the difference between government spending and government revenue – we always have to keep in mind that it has two sides: the real side and the financial side. Whenever the government increases spending, it has two kinds of effects. First, all else equal, it increases the amount of government debt in circulation. And second, it increases demand for goods and services, both directly when the government buys them and indirectly as government spending creates incomes for private businesses and households.
To put it another way, for government to successfully raise spending without raising taxes, two things have to be true. First, someone – banks, wealthy families, foreign countries – has to be willing to hold the additional debt that the government issues. And second, someone has to be prepared to sell whatever it is that the government is trying to buy. If we are asking what kinds of limits there might be to deficit spending, we have to think about both sides. A government’s spending may face financial constraints, if people are unwilling to hold more of its debt; or real constraints, if the economy cannot produce the additional goods and services it is trying to buy.
Some people who think higher deficits are not a problem – particularly those associated with Modern Monetary Theory – believe that the US federal government never faces financial constraints, so only the real constraints matter. Others believe that the federal government might in principle face financial constraints, but there are good reasons to think that they are not an issue today. For policy purposes, the difference between these positions may not be very important.
On the real constraint side, the essential question is how close the economy is to potential output, or full employment. (The two terms are used interchanegably.) In an economy operating at potential, government can only increase its spending f the private sector reduces its spending. This “crowding out” is the real cost of increased public spending. In an economy below potential, on the other hand, the goods and services purchased by increased public spending come from mobilizing unused productive capacity, so there is no crowding out. In. fact, if the fiscal multiplier is big enough (greater than one) then increased purchases of goods and services by the public sector will result in more goods and services being purchased by the private sector as well.
Below, I lay out a baker’s dozen of related arguments for why, from a macroeconomic perspective, we should welcome increased debt-financed public spending. Some people who believe in greater public borrowing would accept all of these arguments; some only some of them.
Real-economy arguments for more public borrowing
1. The economy generally operates below potential. Over the past 30 years, there have been three recessions, each followed by a long period of weak growth and high unemployment. By official measures, in 10 of the past 30 years GDP has been at least two points below potential; there have been only six months when it was more than two points above potential. And there has been no periods of high inflation. This suggests that in general, the economy is not running at full capacity; there is additional productive potential that could be mobilized by higher public spending, without crowding out private spending. In that sense, there is no real cost to higher public spending, and no need top offset it with higher taxes. Even better, higher public spending will help close the output gap and raise private spending as well.
2. There are long run forces pushing down demand. Larry Summers famously reintroduced into the economic conversation the idea of secular stagnation – that there is a long-run tendency for private spending to fall short of the economy’s productive potential. There are many reasons we might expect private spending to be lower, relative to national income, in the future than in the past. Among these: increased monopoly power; the shift toward information-based rather than resource-intensive production; increased shareholder power; a more unequal distribution of income; slower population growth; and the satiation of demand for market consumption, in favor of leisure and nonmarket activities. (The first three of these factors tend to reduce investment spending, the lastthree consumption spending.)If this idea is correct, the demand shortfalls of the past thirty years are not an anomaly, and we should expect them to grow larger in the future.
3. Potential output is mismeasured; we are still well below it. Even by the conventional measures of unemployment and potential output, the US economy has spent far more time in recent decades below target than above it. But if the target is mismeasured, the problem may be even worse. There are good reasons to think that both productivity and laborforce growth over the past decade have been depressed by weak demand. If this is the case, the US economy even at the height of a supposed boom, may in fact be operating well below potential today. The fact thateven with measured unemployment below 4 percent wage growth has accelerated only modestly, and inflation has not accelerated at all, is important evidence for this view.
4. Recessions and jobless recoveries have occurred repeatedly in past, will occur again in the future. Whether or not the US economy is at potential today, the current expansion will not continue forever. Recessions have occurred in the past and will occur in the future. Many forecasts believe there is a high risk of recession is likely in the relatively near future; the fact that the Fed is moving toward cutting rates suggests that they share this view. When thinking about what fiscal balance is appropriate, we need to consider not just where the economy is today but where it is likely to be in coming years.
5. Monetary policy is not effective at maintaining full employment. In the past, weak demand and recessions weren’t considered an argument for more public spending because it was assumed that a central bank following the correct policy rule could quickly return the economy to full employment. But it is increasingly clear that central banks do not have the tools (and perhaps the willingness) to precent extended periods of weak demand. It is increasingly recognized that fiscal policy is also required to stabilize demand. In his July testimony before Congress, Fed chair Jerome Powell said explicitly that in the event of another deep recession, the Fed would need help from fiscal policy. One important reason for this is the problem of the zero lower bound – since the policy interest rate cannot be set below zero, there is a limit to how far the Fed can lower it in a recession.
6. It’s hard to ramp up public spending quickly in recession. Orthodox opinion has long been that fiscal policy is not as effective as monetary policy in a recession because it takes much longer to ramp up public spending than to cut interest rates. While the experience of the Great Recession undermined conventional wisdom on many points, it supported it on this one. The ARRA stimulus bill was supposed to direct spending to “shovel-ready” projects, but in fact the majority of the infrastructure spending funded by the bill came several years after it passed. There are many institutional obstacles to increasing public spending rapidly. This means that if we need higher public spending in a recession, the best thing is to have higher spending all the time. If that leads to an overheating economy in the boom, that is an easier problem for the Fed to solve then a deep recession.
7. The costs of getting demand wrong are not symmetrical. Traditionally policymakers have defined their goal as keeping output as close to potential as possible. But it is increasingly clear that the costs of demand falling short are greater than the costs of demand overshooting potential. One reason for this is the previous point – that conventional policy has an easier time reining in excessive demand than stimulating weak demand. (As the old saying has it, “you can’t push on a string.”) A second reason is that demand has effects that go beyond the level of output. In particular, strong demand and low unemployment redistribute income toward workers from owners, and toward lower-wage workers in particular. Periods of weak demand, conversely, reduce the share of income going to workers. If we think the upward redistribution of income over the past generation is a problem, we should prefer to let demand overshoot potential than fall short of it.
8. Weak demand may have permanent effects on potential output. Traditionally, economists saw the economy’s long-term growth as being completely independent of demand conditions. People spending more money might raise production and employment today, but the long-term growth of potential output depended on structural factors – demographics, technological change, and so on. More recently, however, there has been renewed interest in the idea that weak demand can reduce potential output, an effect known as hysteresis. high unemployment may lead more people to drop out of the laborforce, while low unemployment may lead more people to enter the laborforce (or immigrate from abroad.) Strong demand may also lead to faster productivity growth. If hysteresis is real, then demand shortfalls don’t reduce output and employment this year, but potentially many years in the future as well. This is another reason to be more worried about demand falling short than overshooting, hence another reason to prefer a more expansionary fiscal stance, which normally implies more public borrowing.
Financial arguments for more public borrowing
9. With low interest rates, debt does not snowball. Traditionally, concerns about the financing of government spending have focused on whether debt is “sustainable” – whether debt levels will stabilize as a fraction of GDP, or rise without limit. When interest rates are greater than GDP growth rates, this implies a hard limit to government borrowing – to keep the debt-GDP ratio on a stable path, a deficit in one year must be made up for by a larger surplus in a future year. Otherwise, the interest on the existing debt will imply more and more borrowing, with the debt-GDP ratio rising without limit. But when interest rates on government debt are below growth rates, as they have been for the past 25 years, the debt ratio will stabilize on its own – deficits do not have to be offset with surpluses. This makes much of the earlier concern with debt sustainability obsolete.
10. There is good reason to think interest rates will remain low. There are a number of reasons to think that interest rates on public debt are likely to remain low, even if debt ratios rise considerably higher. First, low interest rates reflect the conditions of chronic weak demand discussed above, for two reasons. First, low investment means less demand for borrowed funds. And second, weak demand means that the interest rate set by the central bank is likely to be low. A second reason to expect low interest rates to continue is that the past ten years have repeatedly falsified predictions of bond vigilantes driving up the rates on government debt. Prior to the financial crisis of 2007-2008, many observers expected a catastrophic flight by investors away from US government debt and the dollar, but in fact, the crisis saw a steep fall interest rates on government debt and a rise in the dollar, as investors all over the world rushed to the safety of Treasury debt. Similarly, in Europe, even in the worst crisis-hit countries like Greece, interest rates are at their lowest point in history. Similarly Japan, with one of the highest debt0-GDP ratios ever recorded (about triple that of the US) continues to borrow at very low rats. Third, the experience of the past ten years have made it clear that even if investors were to demand higher interest rates on government debt, modern central banks can easily overcome this. The most dramatic illustration of this came in the summer of 2012, when a public statement by European Central bank chief Mario Draghi “we will do whatever it takes, and believe me, it will be enough”) reversed the spike in interest rates in countries like Italy, Spain and Portugal practically overnight. Finally, the prices of bonds — with hardly any premium for 30 year bonds over 5 and 10 year maturities — show that private investors do not expect a rise in interest rates any time in the foreseeable future.
11. With hysteresis, higher public borrowing can pay for itself. Even if we are concerned about lowering the debt-GDP ratio, the existence of hysteresis (point 8 above) means that cutting public borrowing is necessarily the right way to get there. In a world where the long-term path of GDP depends on aggregate demand, austerity can be self-defeating even in its own narrow financial terms. If lower public spending reduces demand, then it can lead to lower GDP, potentially raising the debt to GDP ratio even if it succeeds in reducing debt. Greece offers a clear example of this – the fiscal surpluses between 2010 and 2015 succeeded in reducing government debt by 5 percent, but the deep austerity contributed to a fall in GDP of 25 percent. So the debt-GDP ratio actually rose. Similarly, if debt-financed public spending leads to faster growth, the debt-GDP ratio may end up lower than otherwise.
12. Federal debt is an important asset for financial markets. The points up to now have been arguments for why higher public debt is acceptable. But there is also an argument that increased public debt would be a positive good. Financial markets depend on Treasury debt as a safe, liquid asset. Federal government debt offers an absolutely safe asset that can always be sold quickly and at a predictable price – something that is extremely valuable for banks and other financial institutions. There is a strong argument that the growth of the mortgage-backed security market in the 2000s was fundamentally driven by a scarcity of government debt – many financial institutions wanted (or were compelled by regulation) to hold a substantial amount of ultrasafe, liquid debt, and there was not enough government debt in circulation to meet this demand. So financial markets came up with mortgage-backed securities as a supposed alternative – with disastrous results. Similarly, after the recession, one argument for why the recovery was so slow was a “safe asset shortage” – financial institutions were unwilling to make risky loans withoutholdings of ultrasafe assets to balance them. While these concerns have receded today, there is still good reason to expect a “flight to safety” toward Treasury debt in the event of a new crisis, and government debt remains important for settling many financial contracts and pricing other assets. So strange as it may sound, there is a serious argument – made by, among others, Nobel prize winner Jean Tirole in his book on financial liquidity — that increased government borrowing would make the financial system more stable and increase access to credit for other borrowers.
13. Federal debt is an important asset for the rest of the world. Federal debt is an important asset not just for the US financial system, but for the rest of the world. In today’s dollar-based international system, the great majority of international trade and investment is denominated in dollars, and most foreign-exchange transactions involve dollars. As a result, central banks (and private financial institutions) all over the world hold foreign-exchange reserves primarily in the form of dollars. These dollar reserves are mainly held in the form of Treasury debt. Close to half of federal debt is now held abroad, mainly as reserves by foreign governments. These holdings are essential for the stability of the international financial system – without adequate reserves, countries are vulnerable to sudden flows of “hot money” out of their countries. As Barry Eichengreen – perhaps the leading economic historian of the international financial system, — has noted, a deep market for government is an essential requirement for a currency to serve as the global reserve currency. If the US is going to be a responsible partner for the rest of the world — and continue reaping the benefits of being at the center of the global economy — it needs to provide an adequate supply of safe government debt for the rest of the world to hold as reserves.
(I wrote this document for internal use at the Roosevelt Institute. Figured I might as well put it up here as well. Obviously it would benefit from links to supporting material, which I may add at some point.)
