A bridge over the macroeconomic divide

No one can deny that Paul Krugman is a gifted expositor of economic ideas. His column today, "Death by Hawkery," constitutes a fine example of this skill in action.

What I found most interesting in this column is something that would have almost surely escaped his average reader. In particular, I noticed that in telling his basic story, he appealed to a mathematically explicit model of credit cycles written by Nobu Kiyotaki and John Moore (JPE 1997).

Why do I find this interesting?

Well, first of all, I notice that at the time, Kiyotaki was affiliated with that great "freshwater macro" department at the University of Minnesota. You will also notice that the arch-devil Ed Prescott is thanked (among others) for his "thoughtful comments and help" on the paper.

I mention this because I think that Krugman has in the past overemphasized the disagreement that exists among the newer cohorts of macroeconomists (one could make the case that disagreement was much greater in the past); see, for example, here: Disagreement Among Economists. On this matter, I side with Steve Williamson, who I think has rightly taken Krugman to task on this issue; see here and here.

Secondly, I find it interesting that the mechanism highlighted by Kiyotaki and Moore in no way relies on nominal or real price rigidities. It is, in fact, a real business cycle model. Yes, you heard me correctly: Paul Krugman is appealing to an RBC model to help him account for recent events. (Granted, it is an RBC model that incorporates limited commitment, a friction that plays a prominent role in all modern macro theory; see my post here: Asset Shortages and Price Bubbles: A New Monetarist Perspective).

I think this constitutes evidence that the great macroeconomic divide is not as great as it is sometimes portrayed. Most of the disagreement I am aware of is of the gentlemanly "let us agree to disagree" type. But there is no fundamental disagreement in basic macroeconomic methodology among most academic macroeconomists. (There are, of course, healthy and welcome challenges from the fringes of the profession.)

Now for some comments on the economic ideas.

As you may have gathered from my previous post, I am generally sympathetic to the idea of expanding the supply of U.S. treasury debt at this time (with a commitment to unwind in the future, if and when economic conditions improve). Of course, a big question is what to do with the funds acquired in this manner. I'm with Krugman in that heck, we may as well use it to build physical capital (public infrastructure). Financing a corporate tax cut to stimulate domestic private capital spending might be a good idea too (not so politically popular though).

These provisional policy recommendations suggest themselves to me by way of a class of "new monetarist" models that I like to use to organize my thinking about things. But I should say, however, that I'm still not sure just how seriously to take these models (at least, their current incarnations). I'm still a little sketchy about how one might plausibly generate negative real rates of interest in these models; that is, models that take seriously the intertemporal production capabilities of actual economies (you will note that Krugman abstracts from physical capital in telling his little story).

I can't help but note that this same class of models might be used instead to support "conservative" policies. In particular, one force that can potentially drive the expected marginal product of capital (real interest rate) lower is the rational (or irrational) expectation of a future regulatory/tax burden paid for by capital accumulators of all types (including human capital).

If (and I emphasize the if) this is the (or a significant part of the) fundamental problem (and how do we really know that it is not?), then it is hard to see how treasury debt expansion and/or inflationary policy is going to solve it. Fixing the problem in this case means providing an environment that rewards private investment. Death by Dovery is also a possibility. 

Not enough U.S. debt?

One way to measure the ability to service debt is to compute a debt-to-income ratio. Suppose, for example, that your income is $50K per year, that your home is worth $200K, and that you have a $150K mortgage. Then your debt-to-income ratio is 150/50 = 3; or 300%.

Similarly, one way to measure the ability of a country to service its national debt is to compute debt-to-GDP (a measure of domestic income) ratio. The ratio of U.S. federal debt to GDP is currently close to 100%.

Of course, what has a lot of people worried is not the level, but the trajectory, of this ratio. Clearly, the debt-to-GDP ratio cannot rise forever.

No, but on the other hand, there is some evidence to suggest that it can feasibly go much higher. (Whether it should be permitted to do so is a different question, of course.)

Before I go on, I want to clear up a misguided analogy that I frequently hear repeated. The misguided analogy is the idea of the government behaving like a household running up a massive amount of credit card debt.

If this is the way you like to think about things, let me ask you this: Which of your credit cards charge you 0% interest? I ask because that is the interest rate creditors around the world are willing to lend to the U.S. federal government. And what sort of credit card company starts to reduce the interest it charges on your debt as you become progressively more indebted (see the figure above)?

In fact, the terms are even much better than 0%. The real cost of borrowing is measured by the real (inflation adjusted) interest rate. As the figure above shows, the real cost of borrowing has plummeted over the last decade for the U.S. government. As the following figure shows, the U.S. government can now borrow funds for 10 years at close to zero real interest. It can borrow funds for 5 years at a negative real interest.

Now, a negative real rate of interest is a pretty cool deal. Imagine importing 100 bottles of beer from China today, and having to return only 99 bottles next year. If the interest rate remains unchanged one year from now, you can rollover your debt and make a profit. For example, you could borrow another 100 bottles of beer from China, use 99 of these bottles to pay off your maturing obligation, and then drink the remaining beer for free. (Of course, domestic beer brewers would become upset at the lack of demand for their own product, but maybe they can be bribed with free Chinese beer?)

Before we get too carried away, however, I explain here why these very low real rates constitute bad news.

Why are real rates so low?

My own view is that this phenomenon, at its root, has little to do with Federal Reserve or Treasury policy. I believe that the decline in real rates on U.S. treasuries reflects a steady change in how agents and agencies around the world want to structure their wealth portfolios. There has been a massive substitution away from many asset classes into U.S. treasuries; and it is this fundamental market force that is driving real interest rates lower.

The phenomenon began in the early 1990s, with the collapse of the Japanese stock market. Then Mexico in 1994, the Asian crisis 1997-98, Russia in 1998, and Brazil in 1999; see Bernanke (2005). Investors became rationally pessimistic about the returns to investing in these countries, as well as similar countries that had not yet experienced crisis. The natural effect of this would be capital outflows from these countries into relative safe havens, like the United States.

The basic thesis here is very much related to what Ricardo Caballero calls a "global asset shortage." See his discussion here and here; and my own discussion here and here.

The global investment collapse associated with the recent recession has pushed already low real rates lower still. There has been a flight to U.S. treasuries not only by foreigners, but this time by Americans too. Evidently, the perceived return to domestic capital spending remains low. (Some basic theory available here.)

Policy 

Given this pessimistic outlook, it seems unclear what monetary policy can do (the Fed is largely limited to swapping low interest currency for low interest treasuries).

I do, however, believe that there may be a role for the U.S. treasury (in principle, at least). In particular, given the huge worldwide appetite for U.S. treasury debt (as reflected by absurdly low yields), this is the time to start accommodating this demand. Failure to do so at this time will only drive real rates lower. For a world economy that is reasonably expected to grow, negative real interest rates imply a dynamic inefficiency. In short, this is the time to start raising real rates, not lowering them (real rates theoretically rise when new debt crowds out private capital, but note that new debt can also be used to finance corporate tax cuts to stimulate investment, if so desired).

Of course, what theory also tells us is that the government should also be prepared to reverse this recommended debt expansion (assuming that tax rates remain unchanged) once the domestic and world economy return to normal. One may legitimately question whether the government can be expected to make these cuts at the appropriate time. If the government lacks credibility along this dimension (or if future governments cannot be expected to abide by policies put in place by previous governments), then political forces may emerge to block an otherwise socially desirable debt expansion. Perhaps this is one way to interpret recent events.

Fiscal multipliers: another caveat

James Hamilton reminds us of what all Econ 101 students learn (or are supposed to learn) about the peculiarities of national income and product accounting and the caveats that need to be kept in mind when equating the measured GDP to true economic activity. The lesson is hammered home by Yoshiyasu Ono in this paper The Keynesian Multiplier Effect Reconsidered published earlier this year. Here is Hamilton's nice summary of the paper:

According to traditional Keynesian models, even for the case of a completely useless government project, if we were to raise private-sector taxes by just the amount needed to pay the salaries of the hole-diggers, GDP would increase, with a balanced-budget multiplier of one. Yet, Professor Ono asks, how could paying the crew a salary to dig a useless hole possibly lead to an improvement in welfare relative to simply handing them a direct transfer and allowing them to spend more time safely and comfortably at home with the family? And, to make things very simple, if the source of funds for paying the workers was in fact a tax levied on those same individuals, how could we possibly conclude that the enterprise has increased total national income?  

The answer is, we include government spending, even on useless projects, in the definition of GDP, and assume that the value of what is produced is the dollar sum that the government paid for it. The reason even useless government spending has a balanced-budget multiplier of one is that we now have a filled-in hole that we didn't have before. So we have more goods and services (in the form of a newly filled-in hole) than we used to, and impute the value of this new extra stuff as added income for the nation as a whole.

To understand what underlies this phenomenon, we have to revisit the definition of GDP. The Gross Domestic Product is defined as the market-value of all final goods and services produced by domestic factors of production over some specified time period.

It is also useful to keep the following in mind. All production is, by definition, sold (inventory accumulation is treated as a capital expenditure). Therefore, total output equals total expenditure. Moreover, as any expenditure on one side of a transaction constitutes income on the other side, it follows that total expenditure equals total income. To summarize:

 Output (GDP) is equivalent to Expenditure is equivalent to Income

Just to be clear, this is not a theory. It is an accounting identity (something that is true by definition). Now let me work through a series of examples.

First, suppose that a firm pays a worker $1 to produce an object that has a market value of $2. What is the contribution to GDP? The answer is $2. There are two ways to see this. First, the market-value of what has been produced/sold is $2. Second, total income has increased by $2. (Labor income has increased by $1 and profit income has increased by $1).

Now, suppose that a firm pays a worker $1 to produce an object that has a market value of $0. What is the contribution to GDP? The answer is zero. Again, there are two ways to see this. First, the market-value of what has been produced is zero. Second, while it is true that the income of the worker has increased by $1, this income gain is offset exactly by a $1 income loss for the firm. All that has happened in this example is a transfer of purchasing power from the firm to the worker. This is redistribution, not production.

Next, suppose that the government pays a worker $1 to produce an object that has a market value of $0. What is the contribution to GDP? The true contribution is zero. But that's not how the contribution will be measured in the NIPA. The NIPA assumes that the market value of the object produced by (or on behalf of) the government is $1. All that has happened in this example is a transfer of purchasing power from the taxpayer to the worker. This is redistribution, not production. But it will nevertheless be measured as production.

Why does this happen? Is someone trying to pull the wool over our eyes? No. As it turns out, many of the government services produced by government workers are provided for "free" and are hard to value at market prices (national defense is a classic example). When this is the case, it does not seem unreasonable to impute the market-value of a non-priced service by the cost of production.

Having said this, the lesson here is that one should nevertheless use caution in interpreting the estimated multiplier effects of fiscal stimulus programs using historical data as indicators of the likely impact of contemporaneous spending measures on true (as opposed to measured) GDP. The estimates are surely biased upward, although by how much likely depends on the exact nature of the expenditure.

What I have just described is a caveat for those who are inclined to perform cost-benefit exercises using "Keynesian" multiplier analysis. This type of analysis emerged out of a static model (the Keynesian Cross), where the benefit of a $1 expenditure by the government had to exist contemporaneously (there is no explicit future in a static model), which explains why the existence of multipliers greater than unity are so important in this way of thinking about things.

There is a better way of evaluating the net benefit of a government stimulus program. This involves estimating the expected net present value of the program (easier said than done, of course). With the real return on U.S. Treasuries so low (see my previous post), with U.S. infrastructure reportedly in a sorry state, and with so many unemployed construction workers, I would be surprised to learn that there are few positive NPV infrastructure projects currently available.

Unfortunately, political shenanigans (from all sides) sometimes make a mockery out the attempt to estimate NPV in a systematic and unbiased manner. We appear to be living in such times.

Negative real interest rates

The nominal interest rate is a relative price. It is the price of a dollar today measured in units of (the promise of) future dollars. For example, if the risk-free annual interest rate on a U.S. treasury is currently 5%, then one dollar today is valued at 1.05 future (one year from now) dollars.

Current dollars usually trade at a premium relative to future dollars; the degree of this "impatience" is reflected in the nominal interest rate. The higher the nominal interest rate, the more money is valued today vis-a-vis future money. A high nominal interest rate reflects the market's strong desire to have you part with your money today (in exchange for a promise of future money). Conversely, a low nominal interest rate reflects the market's ambivalence about where to allocate dollars across time. A zero nominal interest rate means that the market values current and future dollars equally. To the extent that it is costless to store cash over time, the nominal interest rate is bounded below by zero. This "fact" is sometimes referred to as the zero lower bound.

In macroeconomic theory, the nominal interest rate plays second-fiddle to the so-called real interest rate. The real rate of interest is also a relative price. It is the price of output today measured in units of future output (think of "output" as consisting of an expenditure-weighted basket of commonly purchased consumer goods and services.) So, if the risk-free annual interest rate on an inflation-indexed U.S. treasury is 2%, then one unit of output today is valued at 1.02 units of output in the future.

In the same way that the nominal interest rate measures the relative scarcity of money across time, one can think of the real interest rate as reflecting the relative scarcity of output across time. Economists typically focus on the real interest rate because people presumably care about output and not money (they care about money only to the extent that it may be used to purchase output).

Current output usually trades at a premium relative to future output; that is, the real interest rate is usually positive. The higher the real interest rate, the more output is valued today vis-a-vis future output. A high real interest rate reflects the market's strong desire to have you part with your output today (in exchange for a promise of future output). Unlike the nominal interest rate, however, there is nothing that naturally prevents the real interest rate from becoming negative; see Nick Rowe. And indeed, this appears to have happened recently in the U.S. The following diagram plots the real interest rate as measured by the n-year treasury inflation-indexed security (constant maturity) for n = 5, 10, 20; see FRED.

Prior to the Great Recession, real interest rates are hovering around 2% p.a. and the yield curve is upward sloping (long rates higher than short rates), at least until early 2006 (when it flattens). Following the violent spike up in real interest rates (associated with the Lehman event), real interest rates have for the most part declined steadily since then. The 20 year rate is below 1%, the 10 year rate is basically zero, and the 5 year rate is significantly negative. What does this mean?

The decline in real rates that has taken place, especially since the beginning of 2011, is a troubling sign. A negative 5-year rate implies that current output is now less valuable than future (5 year) output. In other words, (claims to) future output are now trading at a premium. This premium may be signalling an expected scarcity of future output. If so, then this is a bearish signal.

The decline in market real interest rates is consistent with a collapse (and anemic recovery) of investment spending (broadly defined to include investments in job recruiting). For whatever reason, the future does not look as bright as it normally does at the end of a recession. To some observers, this looks like a "deficient aggregate demand" phenomenon. To others, it is the outcome of a rational pessimism reflecting a flow of new regulatory burdens and a potentially punitive tax regime. Both  hypotheses are consistent with the observed "flight to safety" phenomenon and the consequent decline in real treasury yields.

Unfortunately, the two hypotheses yield very different policy implications. The former calls for increased government purchases to "stimulate demand," while the latter calls for removing whatever barriers are inhibiting private investment expenditure. There seems to be room for compromise though. Surely there are public infrastructure projects that can be expected to yield a real return higher than zero? This is a great time for the U.S. treasury to borrow (assuming that borrowed funds are not squandered, of course).

In the event of an impasse, can the Fed save the day? It is hard to see how. The Fed's influence on real economic activity is usually thought to flow through the influence it has (or is supposed to have) on the real interest rate. One could make the case that real interest rates are presently low in part owing to the Fed's easing policies. But this would be ignoring the fact that the Fed's easing policies were/are largely driven by the collapse in investment spending. (I am suggesting that in a world without the Fed, these real interest rates would be behaving in more or less the same way.)

In any case, real interest rates are already unusually low. How much lower should they go? Is it really the case that our economic ills, even some of them, might be solved in any significant manner by driving these real rates any lower? My own view is probably not. If there is something the Fed can do, it is likely to operate through some other mechanism. The problem is not that real interest rates are too high. The problem is that they are not high enough (the robust economic prospects that push real rates higher appear to be absent).

Most Fed types probably hold the view that the main goal of monetary policy is to keep inflation low and stable so as to "anchor" inflation expectations; see James Hamilton on Ben Bernanke's 2007 inflation expectations speech. Bernanke defines well-anchored inflation expectations as being "relatively insensitive to incoming data."

We can compute a market-based measure of inflation expectations using a no-arbitrage-condition which states the the real rate of return on nominal and inflation-indexed treasuries should be roughly equal (the Fisher equation). The relevant nominal interest rates are plotted here:

Next, take the nominal interest rate above (at a given horizon) and subtract the corresponding real interest rate from the first diagram to get:

According to this data, the sharp spike up in real interest rates in the depths of the financial crisis stemmed entirely from a precipitous decline in longer-horizon inflation expectations. While inflation expectations appear to have rebounded to their more normal range of 2-3%, they continue to be more volatile than before the recession.

On the other hand, there is no evidence to suggest that inflation expectations are whirling out of control, one way or the other. I'm not sure to what extent this constitutes success. At the very least it is not utter failure.

Am off to Vancouver now for the 25th Annual CMSG! 

What went wrong at MF Global

Here is a nice quick summary of what went wrong: CNBC video (short, sweet, and to the point.)

It's the same old song. Big financial firm makes a big bet. Information flows relating to probable payoffs suddenly signal higher risk. Rating agencies move in to downgrade firm's liabilities. A "run" ensues (widespread redemptions) leading to...a liquidity event? or a solvency event? (only time will tell, I suppose.)

Why does MF Global matter? One reason is that the institution was added to the Fed's list of 22 primary dealer banks just 8 months ago. See WSJ article below.

Fed Takes Collateral Damage in MF Global Meltdown

WSJ Tue, 1 Nov 2011 698 words

By Min Zeng November 1, 2011, 10:16 AM ET The Federal Reserve is among those feeling the pinch from the collapse of MF Global Holdings Ltd., which only eight months ago was added to the Fed’s list of 22 primary dealer banks. MF Global’s spectacular downfall seems unlikely to pose a systemic financial risk to either the U.S. economy or the Fed, in sharp contrast to the fallout from Lehman Brothers in 2008. But it’s possible it will make the selection procedure tougher for primary dealers, an elite group of institutions with which the New York Fed conducts monetary policy and which are obligated to participate in U.S. Treasury debt auctions. MF Global’s fortunes quickly went downhill over the past week amid concerns over its exposure to the euro zone’s sovereign debt. In this way, its travails underscore the potential contagion risks to the U.S. financial system via the primary dealer network. Besides MF Global, several primary dealers are owned by big European banks, including France’s BNP Paribas SA and Societe Generale SA, whose shares sold off in September due to concerns about their exposure to debts in Greece and other heavily indebted euro-zone sovereigns. “At the very least these applications will undergo a much more stringent vetting procedure,” said Chris Rupkey, senior financial economist at Bank of Tokyo-Mitsubishi UFJ Ltd. in New York. “The lesson of history after these sudden financial bankruptcies is that regulators come down harder than ever. They don’t want to see another MF Global again on their watch.” The Fed may need to increase the standards of its scenario analysis when determining the balance-sheet strength of the primary dealers, said Adrian K. Miller, senior fixed income strategist at Miller Tabak Roberts Securities LLC in New York. A spokesman from the New York Fed declined to comment Monday afternoon. The Fed had already tightened conditions for selecting dealers. The latest revision came in January 2010, which included an increase in capital requirements from $50 million to $150 million. On that basis, some believe the Fed can’t be faulted for having one of its dealers go bankrupt. “No one can hold the Fed responsible for the risk of the firm,” said Michael Franzese, head of Treasury trading at Wunderlich Securities in New York. “You try and put adequate procedures in place so it doesn’t happen but you have to trust people to do the right thing.” Firms that have been seeking to join the primary dealer list include Toronto-Dominion Bank, the second-largest bank in Canada, and CRT Capital, a Connecticut-based broker dealer. Membership has proven profitable at time when Treasury volumes have increased and demand for Treasury bonds has been fueled by the more conservative strategies of investors spooked by the euro-zone crisis and by the Fed’s support for the market. After naming MF Global and Societe Generale to the list in February, earlier this month the Fed added BMO Capital Markets Corp. and Bank of Nova Scotia, both of Canada, boosting the dealer number to 22. Now, with MF Global’s exit leaving a space open, other prospective dealers could campaign for entry, knowing that the central bank needs an enlarged pool to facilitate the giant bond transactions it undertakes to channel monetary stimulus into the economy, according to market analysts. The Fed at the start of this month launched “Operation Twist” — a $400 billion operation to run until mid-2012 through which it will sell short-dated Treasurys and buy those with maturities of between six years and 30 years. Those transactions will be carried out via primary dealers. Primary dealers will also be needed once the Fed starts to withdraw the cash it pumped into the banking system over the past few years, a strategy that has swollen the central bank’s balance sheet to beyond $2 trillion from less than $900 billion shortly before the 2008 financial crisis. The Treasury Department has an interest in sustaining a large membership list for primary dealers, too. It needs these institutions to underwrite government bond sales as it continues to announce giant auctions to fund the fiscal deficit. If the auctions don’t go smoothly, the Treasury’s borrowing costs will rise.