Believe those who are seeking the truth. Doubt those who find it. Andre Gide

## Wednesday, September 9, 2020

### Cochrane on debt II

Yesterday, I posted a reply to John Cochrane's Sept 4 post on the national debt. John alerted me to his Sept 6 update, which I somehow missed. Given this update (together with some personal correspondence), let me offer my own update.

John begins with an equation describing the flow of government revenue and expenditure. With a debt/GDP ratio of one, the sustainable (primary) deficit/GDP ratio is given by g - r, where g = growth rate of NGDP and r = nominal interest rate on government debt (I include Federal Reserve liabilities and currency in this measure). John assumed g - r = 1% (so about \$200B). In a post I published last year, I assumed g - r = 3% (so about \$600B); see here: Is the U.S. Budget Deficit Sustainable?

Two things to take away from these calculations. First, this arithmetic suggests that the U.S. federal government can easily run persistent primary budget deficits in the range of 1-3% of GDP. Not only does the debt not need to be paid off, but it can grow forever. Second, primary budget deficits are presently far in excess of this range. What does this imply?

Let's step back and think about John's equation. The arithmetic of the government "budget constraint" basically says this:

Deficit/GDP = [1 - (1+r)/(1+g)] x Debt/GDP

Note that a sustainable primary deficit is only possible if r < g. If r > g, then a primary surplus is needed to service the interest expense of the debt.

Students of monetary theory may recognize the expression above as a Laffer curve for inflation finance. That is, in the case of currency we have r = 0. Let g represent the growth rate of the supply of currency and assume a constant RGDP (so that g also measures the growth rate of NGDP). Finally, replace debt with currency, so that

Seigniorage revenue = [1 - 1/(1+g)] x Money/GDP

Again, this is just arithmetic. Economic theory comes in through the assumption that the demand for money is decreasing in the rate of inflation, g. If this is true, then an increase in g has two opposing effects: it increases seigniorage revenue by increasing the inflation tax rate, but it lowers seigniorage revenue because it decreases the inflation tax base. There is a maximum amount of seigniorage revenue the government can collect by printing money. That is, there are limits to inflation finance. (See also my post here.)

Now, I know John is fond of saying that Federal Reserve liabilities and U.S. Treasury securities are essentially the same thing (especially if the former exist mainly as interest-bearing reserve accounts). I happen to agree with this view. But then we can use exactly the same logic to characterize the limits to bond finance, recognizing that U.S. Treasury securities are essentially money. To this end, assume that the Debt/GDP ratio is an increasing function of (r - g). To make things a little simpler, let me continue to assume zero RGDP growth, so that g represents both inflation and NGDP growth. Finally, let me assume that r is a monetary policy choice (just as setting r = 0 for currency is a policy choice).

Next, we need a theory of inflation. In the models I work with, the rate of inflation in a steady state is determined by the growth rate of the nominal debt, g, which I also treat as a policy parameter. So, the magnitude r - g is policy-determined, at least, within some limits. By lowering r and increasing g, the government is making its securities less attractive for people to hold. But this just tells us that the demand for debt is lower than it otherwise might be--it does not tell us how large this demand is in the first place, or how it is likely to evolve over time owing to factors unrelated to r or g (e.g., regulatory demand, foreign demand, etc.).

So, with this apparatus in place, my interpretation of what worries John is the question of what happens if [1] the federal government finds itself near the top of the bond-seigniorage Laffer curve; and [2] a shock occurs that requires a large fiscal stimulus. Barring alternative forms of securing resources (e.g., through direct command/conscription), the government will not have the fiscal capacity to lay claim against the resources it needs. Printing more money/bonds here is not going to help even with zero interest rates. The ensuing inflation would simply put us on the right-hand-side of the Laffer curve -- the government's ability to secure resources would only diminish

Assuming I have captured at least a part of John's concern accurately, let me go on to critique it. To begin, there's nothing wrong with the logic I spelled out (I don't think). But I want to make a couple of points nevertheless.

First, the demand for U.S. government securities (D/Y) seems to be growing very rapidly and for a very long time now. We know, anecdotally, that the UST is used widely as collateral in credit derivatives markets and repo, that foreign countries view it as a safe asset, that investors value its safety, and that recent changes to Dodd-Frank and Basel III have contributed to the regulatory demand for USTs. The global demand for the U.S. dollar is, if anything, growing more rapidly than ever (re: the recent "dollar shortages" that resulted in the Fed opening its central bank swap lines). We don't know where this limit is, but judging by how low U.S. inflation is (together with low UST yields), it seems fair to day that there's still plenty of fiscal capacity. (And I want to stress that this has nothing to do with the ability of a country to pay back its debt -- I'm not sure why John keeps mentioning this while at the same time understanding that this debt is money).

I suspect that John is likely to agree with what I just said. Sure, there may be more room now, but how much more? With bipartisan concern for debt absent in Congress, with no sign of inflation in sight, with interest rates so low, how can we not hit this limit at some point?

My own view is that we are bound to hit this limit (though, economists like Simon Wren-Lewis have warned me not to discount the forces of austerity). The question is what happens once we hit that limit? I say we get USD depreciation and some inflation (not hyperinflation). John seems to be worried about hyperinflation after all, which he likens to a debt rollover crisis. I just don't see it. (Of course, if John is simply suggesting that the fiscal authority will continue to run persistently large deficits in the face of high inflation, then I agree with him. While I don't see this happening, who can say for sure?)

Finally, what happens if we're near the debt limit and there's a shock. Well, what type of shock exactly? The type of shock that hit us in 2008 is likely to increase the demand for debt, expanding fiscal capacity. So, here too, I'm not sure what form the debt crisis is supposed to take. It would be great to appeal to a model (but please, not one of Greece).

## Tuesday, September 8, 2020

### Cochrane on why debt matters

The stock of national debt is now larger than our annual national income in the United States. Is this something to worry about? Does it matter how big the debt-to-GDP ratio gets? Is there any limit to how large it can grow and, if so, what is it this limit and what factors determine it? A lot of people have been asking these questions lately. John Cochrane is the latest to opine on these questions here: Debt Matters

I'm not even sure where to begin. I suppose we can start with the famous debt clock pictured on the right. Whenever I look at the debt clock, I'm reminded of James Tobin who, in 1949 remarked:

The peace of mind of a conscientious American must be disturbed every time he is reminded that his government is 250 billion dollars in debt. He must be shocked by the frequent announcement that every newborn baby is burdened, not with a silver spoon, but with a debt of \$1700.

The national debt is now 100 times larger than it was in 1949. Society has somehow managed to hold itself together since then. At the very least, this suggests we need not pay attention to the debt clock. It does not, however, not mean we shouldn't pay attention to managing the debt. Ironically, worrying about the debt is, in a way, what permits us not to worry about it. The time to start worrying is when we and our elected representatives stop worrying about it. According to John, "The notion that debt matters, that spending must be financed sooner or later by taxes on someone, and that those taxes will be economically destructive, has vanished from Washington discourse on both sides of the aisle." That is, it may be time to start worrying.

I think there's an element of truth to this. For example, while it's true that the Reagan deficits were large, it's also true that there was strong bipartisan support for "doing something about the growing debt." And it wasn't just words. As Justin Fox reminds us, Congress increased taxes seven times between 1982-93. Well, what about Japan? As I explain here, Japan is a poster child for "worrying about the debt." To make a long story short, the debt-to-GDP ratio in Japan has stabilized (pre-Covid, at least), inflation is below target, and the fiscal authority keeps raising the sales tax. Rightly or wrongly, the Japanese "care" about the national debt--the effect of which is to keep fiscal policy "anchored."

But what exactly is there to fear if fiscal policy becomes "unanchored?" For a country like the United States, it seems clear that outright default will never happen. U.S. Treasury securities (USTs) are too important for global financial markets. A default may very well trigger a global financial meltdown. The only practical option is to continue rolling over the debt, principal and interest (the latter of which is very low these days). Is there a danger of "bond vigilantes" sending the yields on USTs skyward? Not if the Fed stands ready to keep yields low (related post here on yield curve control). And, in any case, even if the Fed raises (or is expected to raise) its policy rate, the U.S. Treasury can just continue to issue the bills necessary to make the scheduled payments. Treasury securities and Federal Reserve reserves are just different forms of interest-bearing money. To put things another way, the national debt need never be paid back--like money, it can be held in private wealth portfolios forever. The only question is on what terms it will be willingly held.

This last point gets to the question of what can be expected to happen if the debt gets too large (say, because the fiscal authority plans to run large primary budget deficits off into the indefinite future). Much will depend on the evolution of the global demand for USTs. If that demand stops growing while fiscal deficits run unabated, surely we can expect the U.S. dollar to weakened and the domestic price-level to rise. The former is likely to contribute to an export boom, which should serve to close the trade deficit (mitigating the adverse consequences of global imbalances). The latter is likely to promote the growth of nominal GDP.

Needless to say, an export boom and higher NGDP growth don't sound like disaster scenarios, especially in the current economic environment. John seems to worry that whatever happens, it's likely to happen suddenly and without warning. We know Naples is going down (in the manner of Pompeii c. 79AD), we just don't know when. But how does the lava flow correspond to the economic consequences of a debt crisis? (Keep in mind, we're not talking about a country that issues foreign-denominated debt.)

Should we be worried about hyperinflation? Evidently not, as John does not mention it (see also this nice piece by Francis Coppola). But he does mention something about fiscal capacity (the ability of the fiscal authority to exert command over resources). As I explain here, there are limits to how much seigniorage can be extracted in this manner. To put things another way, there are economic limits to how large the debt-to-GDP ratio can get. But reaching this limit simply means that the required tax (whether direct or indirect via inflation) is high--it does not mean disaster.

John concludes with the following warning: "The closer we are to that limit, the closer we are to a real crisis when we need that fiscal capacity and its no longer there." This is one of those sentences that starts your head off nodding in agreement. But then you think about it for a minute and wonder what type of "real crisis" he has in mind? If it's a financial crisis, the implied positive money-demand shock (flight-to-safety) is likely to increase fiscal capacity, not diminish it. A war perhaps? In these types of emergencies, the nation bands together and governments use other means to gather the resources necessary (e.g., conscription).

So, to conclude, I'm not saying that John is wrong. It's just not very clear in my mind how he imagines a U.S. debt crisis to unfold exactly. What is missing here is a model. This is odd because one of John's great strengths is model building. And so my conclusion is that it would be very interesting to follow the logic of his argument through the lens of one of his models. Let's see the model, John!

## Friday, September 4, 2020

### The Fed's new monetary policy framework

The Fed's much-anticipated new monetary policy framework is now public. Fed Chairman Jerome Powell outlined the policy framework last week in Jackson Hole; you can view his speech here. Overall, I thought Powell's delivery was very good. While there's room for improvement, I think the new framework is a step in the right direction (George Selgin provides a good critique here). There were three things in Powell's speech that stuck out for me. I discuss these below.

Shortfalls vs. Deviations

At the 22:30 mark, Powell reports what may very well be the most substantive change to the monetary policy statement. Here, he states that the FOMC will now interpret important macroeconomic time-series like GDP and unemployment as exhibiting "shortfalls" instead of "deviations" from some ideal or "maximum" level (a frustratingly vague concept).

The practical effect of this shift is to remove (or make less prominent) in the minds of FOMC members the idea that the economy is, or will soon be, "overheating" (i.e., embarked on an unsustainable path that can only end in misery for those most vulnerable to economic recession).

The idea of "deviation from (some) trend" seems like a plausible description of the postwar U.S. up to the mid-1980s. Severe contractions were usually followed by equally robust recoveries. However, this representation seems to break down since the "great moderation" that began in the mid-1980s. Since then, economic recessions have not been followed by above-average growth. Instead, each recession seems better described as a "growth shortfall." We're not entirely sure what accounts from this cyclical asymmetry, but it seems consistent with Milton Friedman's "plucking model." I think we can expect a stream of research resurrecting this old idea (see here, for example).

In any case, the upshot here is that, to the extent that "overheating" is no longer considered a serious threat, the FOMC will be less likely to implement "preemptive" policy rate hikes. This constitutes a tacit acknowledgement that the period leading up to "lift off" and what followed might have been handled better. As I wrote at the time (see my discussion here), standard Phillips Curve logic did not seem to support tightening (unemployment was above the estimated natural rate, inflation was below target, and inflation expectations were declining). But the Committee somehow talked itself into the need to "normalize," to act preemptively and not get caught "behind the curve." In fairness, monetary policy is always about balancing risks (in this case, the perceived risk of overheating). In the near future, less weight will be assigned to the risk of overheating.

The Maximum Level of Employment

At the 22:30 mark, Powell states "Of course, when employment is below its maximum level, as is so clearly the case now, we will actively seek to minimize that shortfall..."

I have a hard time not interpreting "maximum" here as "socially desirable." I think most people would agree that the 2008 financial crisis caused employment to decline below its maximum level. The workers rendered idle in that episode constituted a social waste, and the Fed was right to loosen monetary policy to stimulate economic activity in the face of recessionary headwinds.

But the recession induced by the C-19 is very different from standard recessions. This was laid out very clearly by St. Louis Fed President Jim Bullard on March 23, 2020: Expected U.S. Macroeconomic Performance during the Pandemic Adjustment PeriodAccording to Bullard, the temporary removal of some workers from their jobs is not, in this case, a waste of resources. The decline in employment in this case should be viewed as an investment in public health. That is, the maximum level of employment declined and its recovery is driven mostly by the contagion dynamic (as well as improvements in social distancing protocols, masking, testing, treatments, etc.). The role of monetary policy here is to calm financial markets (which the Fed successfully accomplished in March) and to aid the fiscal authority with its income maintenance programs. In short, the primary monetary/fiscal policy objective here is to deliver insurance, not stimulus.

Monetary stimulus is appropriate, however, to the extent that demand factors (e.g., individually rational, but a collectively irrational restraint on spending) are inhibiting the recovery dynamic. The evidence for this is usually assumed to be found in falling inflation and inflation expectations, and declining bond yields. And usually, this makes sense, because we usually assume that recessions are caused by collapses in aggregate demand (as in 2008-09). But what if the increase in the demand for money (safe assets in general) is driven by a collectively rational fear? We'd expect to see the exact same inflation and interest rate dynamic, but the role for stimulative monetary policy would be more difficult to justify (though the desirability for insurance remains).

So, maybe it is not so clearly the case now that employment is below or, at least, far below its "maximum" level. Note that a significant part of the decline in aggregate employment is coming from the leisure and hospitality sector:
Arguably, we do not want, at this stage of the pandemic, to promote the indoor dining experiences people enjoyed earlier this year. This activity will return slowly as economic fundamentals improve. The "full employment" level of employment in this sector is clearly below what it was in Jan 2020. But, to be fair, it is entirely possible, and perhaps even likely, that the level of employment even here is lower than the "full employment" level. It's very hard to tell by how much though.

Average Inflation Targeting

At the 24:00 mark, Powell explains how AIT will help anchor inflation expectations. Missing the inflation for a prolonged period of time will cause expectations to drift away from target and line up with the historical experience. This view of expectation formation is firmly rooted in the "adaptive expectations" tradition. That is, expectations are assumed to be formed by looking backward instead of forward

People sometimes claim that adaptive expectations are inconsistent with "rational" expectations. But this is not necessarily the case. In fact, it makes sense to use the historical record of inflation realizations to make inferences about the long-run inflation target if people are not sure of the monetary authority's true inflation target; see, for example, here: Monetary Policy Regimes and Beliefs

It's still not entirely clear to me whether FOMC members view AIT as a policy to pursue passively (i.e., let inflation creep up to and beyond target on its own) or actively (i.e., take explicit actions to promote an overshoot of inflation). If it's the former, then I'm on board with the idea. But if it's the latter, I am not. In particular, with the liquidity-trap-like conditions we're presently in, the Fed does not have the tools (or political will) to boost inflation persistently. It is likely to fail, just as the Bank of Japan failed. (I explain here why it's more difficult for a central bank to raise the inflation target than to lower it.) So, as I've advocated many times in the past, why not just declare 2% as a soft-ceiling and let fiscal policy do the rest?

My view rests on the belief that missing the inflation target from below by 50bp over the past eight years is not a significant macroeconomic problem (especially given how crudely inflation is measured). The FOMC did view it as a problem, but mainly, it seems, because of the embarrassment associated with missing its target. "We are a central bank. We have an inflation target. Central banks are supposed to hit their inflation targets. We need to hit our inflation target to remain credible." This is why earlier FOMC statements emphasized the Fed's "symmetric" inflation target. That did not work and so now we have AIT which, I'm afraid, might not work either. Happily (for those who want to see higher inflation), Congress seems comfortable with the idea of producing large budget deficits into the foreseeable future.

So, if we get higher inflation, it will largely be a fiscal phenomenon. The purpose of AIT is to accommodate any rise in inflation for the purpose of increasing inflation expectations and avoiding the specter of deflation (people often point to Japan as a case to avoid, by Japan seems to be doing fine as far as I can tell). There is the question of how the Fed would react should inflation rise sharply and persistently above 2%. Even if the event is unlikely, it would be good to state a contingency plan. In the past, the Fed could be expected to raise its policy rate sharply. But this event, should it transpire, will almost surely take place during an employment shortfall (since this is now the acknowledged new normal). The only prediction I'll make here is that the FOMC will have a lot of explaining to do in this event.