At The International Economy: How Worried Should We Be about Asset Bubbles?

(I am an occasional contributor to roundtables of economists in the magazine The International Economy. This month’s topic was “What about the Risk of a Bursting Asset Bubble?”, with corporate debt and equity mentioned as possibilities. Contributors were asked to rank their level of concern from 1 to 10. My response is below.)

Any time you have an asset held primarily for capital gains, a story that allows people to extrapolate from recent price increases to future ones, and a reasonably elastic credit system, you have the ingredients for a bubble. The question is not whether there will be bubbles, but how damaging they will be, and what steps we should take if we think one is developing in a particular asset market.

Corporate debt is an unlikely asset for a bubble. Unlike with equity, real estate, or currency, there are clear limits to potential capital gains. High levels of stock buy- backs are problematic for a number of reasons, but they don’t particularly suggest a bubble. When a greater share of corporate value added is paid out to shareholders rather than retained and invested or paid to workers, that may be bad news for the economy in the long run. But it is good news for owners of corporate stock, and there’s nothing strange about it being priced accordingly.

Cryptocurrencies are a better candidate for a bubble. It’s safe to say they are mostly held in expectation of capital gains, since they pay no income and, despite the promises of their boosters, have limited utility for transactions. It wouldn’t be surprising if their value fell to a small fraction of what it is today.

But that brings us to the question of how damaging a bursting bubble will be. The housing bubble was exceptionally damaging because housing is the main asset owned by most middle-class families, housing purchases are mostly debt-financed, and mortgages are a major asset for the financial system. It’s hard to see how a collapse of bitcoin or its peers would have wider consequences for the economy.

The other question is what to do about a bubble if we have reason to believe one is forming. One common answer is to raise interest rates. The problem is that, historically, there’s no sign that low rates are more favorable to bubbles than high ones. The 1980s savings and loan crisis took place in an environment of—indeed was driven by—historically high interest rates. Similarly, Sweden’s great real estate bubble of the late 1980s took place when rates were high, not low.

And why not? While productive investment may be discouraged by high rates, expected capital gains at the height of a bubble are too high for them to have much effect. This was most famously illustrated in the late 1920s, when the Fed’s efforts to rein in stock prices by raising rates did a great deal to destabilize European banks by reversing U.S. capital outflows, but had little or no effect on Wall Street.

A better policy in the face of a developing bubble is to directly limit the use of credit to buy the appreciating asset. Tighter limits on mortgage lending would have done far more than higher rates to control the housing bubble of the 2000s.

In other cases, the best policy is to do nothing. As economists going back to John Maynard Keynes have observed, a chronic problem for our economy is an insufficient level of investment in long-lived capital goods and new technology. To the extent that inflated asset values encourage more risky investment—as in the late 1990s— they may be even be socially useful.

By all means, let’s take steps to insulate the core functions of the financial system from speculation in asset markets. But holding macroeconomic policy hostage to fears of asset bubbles is likely to do more harm than good.

Weighing the chance of a major bubble along with its likely consequences, I’d put my concern over asset bubbles at three out of ten. The biggest danger is not a bubble itself, but the possibility that a fear of bubbles will prompt a premature tightening of monetary policy.

Money and Cryptocurrencies


(This is an edited and expanded version of a talk I gave in Trento, Italy in June 2018, on a panel with Sheila Dow.)

The topic today is “Digital currencies: threat or opportunity?”

I’d like to offer a third alternative: New digital currencies like bitcoin are neither a threat or an opportunity. They do not raise any interesting economic questions and do not pose any significant policy problems. They do not represent any kind of technological advance on existing payment systems, which are of course already digital. They are just another asset bubble, based on the usual mix of fraud and fantasy. By historical standards, they are not a very large or threatening bubble. There is nothing important about them at all.

Why might you conclude that the new digital currencies don’t matter?

– Aggregate size – the total value of all bitcoin is on the order of $200 billion, other digital currencies are much smaller. On the scale of modern financial markets that’s not much more than a rounding error.

– No articulation with the rest of the financial system. No banks or other important institutions rely on cryptocurrencies to settle transactions, or have substantial holdings on their balance sheets. They’re not used as collateral for loans.

– Not used to structure real activity. No significant part of collective productive or reproductive activity is organized by making payments or taking positions in cryptocurrencies.

Besides that, these currencies don’t even do what they claim to do. In practice, digital currencies do depend on intermediaries. Payment is inconvenient and expensive — as much as $14 per transaction, and accepted by only 3 of top 500 online retailers. And markets in these currencies are not decentralized, but dominated by a few big players. All this is documented in Mike Beggs’ wonderful Jacobin article on cryptocurrencies, which I highly recommend.

Compare this to the mortgage market. Total residential mortgages in the US are over $13 trillion, not far short of GDP. The scale is similar in many other countries. Mortgages are a key asset for the financial system, even when not securitized. And of course they play a central role in organizing the provision of housing (and commercial space), an absolutely essential function to social reproduction.

And yet here we are talking about cryptocurrencies. Why?

Partly it’s just hard money crankery and libertarianism, which have a outsized voice in economics discussions. And partly it’s testimony to the success of their marketing machine. One might say that the only thing that stands behind that $200 billion value, is the existence of conversations like this one.

But it’s not just cranks and libertarians who care about cryptocurrencies. Central bank research departments are earnestly exploring the development of digital currencies. This disproportionate attention reflects, I think, some deeper problems with how we think of money and central banking. The divide over whether crypto-currencies represent anything new or important reflects a larger divide over how we conceive of the monetary system.

In the language of Schumpeter — whose discussion in his History of Economic Thought remains perhaps the best starting point for thinking about these things — it comes down to whether we “start from the coin.” If we start from the coin, if we think of money as a distinct tangible thing, a special kind of asset, then bitcoin may look important. We could call this the quantity view of money. But if we follow Schumpeter — and in different ways Hyman Minsky, Perry Mehrling and David Graeber — and start from balance sheets, then it won’t. Call this the ledger view of money.

In the quantity view, “money” is something special. The legal monopoly of governments on printing currency is very important, because that is money in a way that other assets aren’t. Credit created by banks is something different. Digital currencies are a threat or opportunity, as the case may be, because they seem to also go in this exclusive “outside money” box.

But from the Minsky-Mehrling-Graeber point of view, there’s nothing special about outside money. It’s just another set of tokens for recording changes in the social ledger. What matters isn’t the way that changes are recorded, but the accounts themselves. From this perspective, “money” isn’t an asset, a thing, it is simply the arbitrary units in which ledgers are kept and contracts denominated.

The starting point, from this point of view, is a network of money payments and commitments. Some of these commitments structure real activity (I show up for work because I expect to receive a wage). Others are free-standing. (I pay you interest because I owe you a debt.) In either case money is simply a unit of account. I have made a promise to you, you have a made a promise to someone else; these promises are in some cases commitments to specific concrete activities (to show up for work and do what you’re told), but in other cases they are quantitative, measured as a certain quantity of “money.”

What does money mean here? Simply whatever will be accepted as fulfilment of the promise, as specified in whatever legal or quasi-legal provisions govern it. It is entirely possible for the unit of account to have no concrete existence at all. And in any case the concrete assets that will be accepted are never identical; their equivalence is to some extent a fiction enshrined in the terms of the contract, and to some extent the result of active interventions by whatever authorities are responsible for the payments system.

In short, the fact that some particular asset that serves as money in this or that case is not very interesting. What matters is the balance sheets. Money is just a means of recording changes on balance sheets, of making transfers between ledgers. If we take the ledger view, then there’s no difference between physical currency and an instrument like a check. In either case the social ledger maintained by the banking system has a certain credit to you. You want to transfer a part of that to someone else, for whatever reason. So you give that person a piece of paper with the amount written on it, and they take it to their bank, which adjusts the social ledger accordingly. It makes no difference whether the piece of paper is a dollar or euro bill or a check or a money order, any more than it matters what its physical dimensions are or whether it is one sheet of paper or two.

And of course the majority of transactions are made, the majority of obligations, are settled without using pieces of paper at all. In fact the range of transactions you can carry out using the pieces of paper we call “money” is rather limited.

To put it another way: At the train station there are various machines, which will give you a piece of paper while debiting your bank account. Some of those pieces of paper can be used in exchange for a train ride, others for various other purposes. We call one a ticket machine and one an ATM. But conceptually we should think of them as the same kind of machine. Both debit your social ledger and then give you a claim on something concrete — a paper from the newsstand, say, or a train ride, as the case may be.

In the quantity view of money, there is some special asset called money which the rest of the payments system builds off. So the fact that something else could “be” money seems important. It matters that the government has a legal monopoly on printing currency, so it also matters that something like cryptocurrency seems to evade that monopoly. In the ledger view, on the other hand, that legal monopoly doesn’t matter at all. There are lots of systems for making transfers between bank accounts, including many purely electronic ones. And there are social ledgers maintained by institutions that we don’t officially recognize as banks. New digital currencies introduce a few more of each. So what?

In the quantity view, money and credit are two distinct things. We start with money, which might then be lent. This is how we learn it as children. In the ledger view, money is just anything that settles an obligation. And that is constantly done by promises or IOUs. The fact that “banks create money” in our modern economy isn’t some kind of innovation out of an original situation of cash-on-the-barrelhead exchange. Rather, it is a restriction of money-creation from the historical situation where third-party IOUs of all kinds circulated as payment.

Related to this are two different views of central banks. In the quantity view, the fundamental role of the central bank is in some sense setting or managing the money supply. In the ledger view, where money is just an arbitrary subset of payments media, which is constantly being created and destroyed in the course of making payments, “the money supply” is a nonsense term. What central banks are doing in this view is controlling the elasticity of the credit system. In other words, they are managing the willingness and ability of economic units to make promises to each other.

There are a variety of objectives in this; two important ones today are to control the pace of real activity via the elasticity of money commitments (e.g. to keep the wage share within certain bounds by controlling the level of aggregate employment) and to maintain the integrity of the payments system in a crisis where a wave of self-perpetuating defaults is possible.

In either case the thing which the central bank seeks to make more scarce or abundant is not the quantity of some asset labeled as “money”, but the capacity to make promises. To reduce the level of real activity, for example, the central bank needs to make it more difficult for economic units to make claims on real resources on the basis of promises of future payments. To avoid or resolve a crisis the central bank needs to increase the trustworthiness of units so they can settle outstanding obligations by making new promises; alternatively it can substitute its own commitments for those of units unable to fulfill their own.

Now obviously I think the ledger view is the correct one. But many intelligent people continue to work with a quantity view, some explicitly and some implicitly. Why? I think one reason is the historical fact that during the 20th century, the regulatory system was set up to create a superficial resemblance to the quantity theory. The basic tool of monetary policy was restrictions on the volume of credit creation by banks, plus limits on ability of other institutions to perform bank function. But for various reasons these restrictions were formalized as reserve requirements , and policy was described as changing quantity of reserves. This created the illusion we were living in world of outside money where things like seignorage are important.

Axel Leijonhufvud has given a brilliant description of how regulation created this pseudo quantity of money world in several essays, such as “So Far from Ricardo, So Close to Wicksell.”

Now this structure has been obsolete for several decades but our textbooks and our thinking have not caught up. We still have an idea of the money multiplier in our head, where bank deposits are somehow claims on money or backed by money. Whereas in reality they simply are money.

The fact that money as an analytic category is obsolete and irrelevant, doesn’t mean that central banks don’t face challenges in achieving their goals. They certainly do. But they have nothing to do with any particular settlement asset.

I would frame them the problems like this:

First, the central bank’s established instruments don’t reliably affect even the financial markets most directly linked to them. This weak articulation between the policy rates and other rates has existed for a while. If you look back to 2000-2001, in those two years the Federal Reserve reduced the overnight rate by 5 points. But corporate bond rates fell only one point, and not until two years later. Then in 2003-2006, when the Fed raised its rate by 4 points, the bond rates did not rise at all.

Second, neither real economic behavior nor financial markets respond reliably to interest rate changes. It’s a fiction of the last 25 years — though no longer than that — that this one instrument is sufficient. The smugness about the sufficiency of this tool is really amazing in retrospect. But it’s obvious today — or it should be — that even large changes in interest rates don’t reliably affect either the sclae of concrete activity or the prices of other assets.

Third, there is no single right amount of elasticity. A credit system elastic enough to allow the real economy to grow may be too elastic for stable asset prices. Enough elasticity to ensure that contracts are fulfilled, may be too much to avoid bidding up price of real goods/factors.

People who acknowledge these tensions tend to assume that one goal has to be prioritized over the others. People at the Bank for International Settlements are constantly telling us that financial stability may require accepting persistent semi-depression in real activity. Larry Summers made a splash a few years ago by claiming that an acceptable level of real activity might require accepting asset bubbles. From where I am sitting, there are just competing goals, which means this is a political question.

Fourth, the direction as well as volume of credit matters. In discussion like this, we often hear invocations of “stability” as if that were only goal of policy. But it’s not, or even the most important. The importance of crises, in my opinion, is greatly overrated. A few assets lose their values, a few financial institutions go bust, a few bankers may go to jail or leap out of windows — and this time we didn’t even get that. The real problems of inequality, alienation, ecology exist whether there is a financial crisis or not. The real problem with the financial system is not that it sometimes blows up but that, in good times and bad, it fails to direct our collective capabilities in the direction that would meet human needs. Which today is an urgent problem of survival, if we can’t finance transition away from carbon fast enough.

For none of these problems does some new digital currency offer any kind solution. The existing system of bank deposits is already fully digital. If you want set up a postal banking system — and there’s a lot to recommend it — or to recreate the old system of narrow commercial banking, great. But blockchain technology is entirely irrelevant.

The real solution, as I have argued elsewhere (and as many people have argued, back to Keynes at least) is for central banks to intervene at many more points in financial system. They have to set prices of many assets, not just one overnight interest rate, and they have to direct credit to specific classes of borrowers. They have to accept their role as central planner. It is the need for much more conscious planning of finance, and not crypto currencies, that, I think, is the great challenge and opportunity for central banks today.