Archive for the Category Exchange Rates

 
 

We need to unify monetary theory and monetary policy

Before today’s post, a few quick comments.  I have a piece on Trump’s “deregulation” policies at MarketWatch.  I have a Ted talk on public opinion at Econlog.

It’s clear to me that there is something seriously wrong with the field of monetary economics.  The profession got 2008-09 almost entirely wrong.  But it’s hard to pin down exactly where the problem lies.  After all, there are increasingly sophisticated models being developed by economists who are much smarter than me.  These models feature rational expectations, and all the other bells and whistles you might want. I regret their focus on interest rates and inflation, but that doesn’t fully explain the problem.  While I prefer to talk about money and NGDP, anything that I believe can be translated into New Keynesianism by referring to the gap between the natural rate of interest and the market rate.  So where’s the problem?

In my view, the problem lies in the interface between sophisticated theoretical models and a very crude discourse on monetary policy.  This monetary policy discourse is little changed from 90 years ago, and not at all informed by recent developments in theory.

John Hall directed me to a James Hamilton post that included this remark:

Zhang’s suggested solution begins with the observation by Gurkaynak, Sack and Swanson (2005) that the news revealed by a typical FOMC announcement is multidimensional. The Fed is typically both changing the current interest rate and signaling the changes that are in store for the future.

Here’s my hypothesis.  Monetary models suggest that monetary policy actions are multidimensional, while most of the discourse on real world monetary policy treats policy as one dimensional—easier or tighter money, lying along a single line.  This has led to the confusing debate between Keynesians and NeoFisherians, which I’ll return to later.

Once monetary theorists understood that monetary policy actions affected the entire future path of policy, the modeling problem became more difficult.  At this point they should have stopped basing their models on interest rates, as this variable creates all sorts of indeterminacy issues, or perhaps I should say makes these issues even harder to grapple with—they can also occur when using money itself.

To make things simpler, I’m going to boil the multidimensional theoretical models down to two dimensions—levels and growth rates.  Obviously things are more complicated than that, but it’s enough to make my point about the disconnect between monetary theory and the modern discourse on monetary policy.  I’m also going to work with some alternative monetary instruments, that is, alternatives to interest rates.

Let’s start with the monetary base.  Any change in monetary policy has two dimensions, a level shift and a growth rate shift.  Thus the Fed might immediately increase the base by 3%, but not change its expected growth path going forward, or they might keep the level of the base as is, but announce a faster growth path for the base.  In practice, most monetary policy shocks probably involve a bit of each.  You could plot them using a graph with the X axis being the immediate change in the level of the base, and the Y axis being the change in the expected growth rate of the base.

Elsewhere I’ve argued that Keynesian economics is basically about level shifts, and monetarism is basically about growth rate shifts.  But old monetarism is mostly gone, so I’ll instead describe these two dimensions of monetary policy as “Keynesian” and “Fisherian”.  No “neo” is necessary in front of Fisherian, for reasons that will later become clear.

Thus if the Fed suddenly announces a 3% rise in the base, and also announces that henceforth the growth rate of the base will be reduced by 1.8%/year, then the policy would be described as “Keynesian monetary stimulus and Fisherian monetary contraction.”  Terms like “easy money” and “tight money” are no longer sufficient in this multidimensional world.  And keep in mind that this multidimensional approach comes right out of modern monetary theory.  (Not “MMT”, I mean actual cutting edge monetary theory.)

Unfortunately, money demand shocks leave money as an unsuitable instrument for policy analysis.

I eventually plan to link this up to the Keynesian/NeoFisherian debate.  To do so, we’ll run through the exact same exercise, but this time using the exchange rate as the policy instrument.  (As is the case in Singapore, for instance.)  A Keynesian policy change is a one time adjustment in the exchange rate.  A Fisherian policy change is a change in the expected growth rate of the exchange rate.  In the Dornbusch overshooting model, an increase in the money supply causes a fall in interest rates (to levels below the alternative currency.) This leads to a one-time depreciation in the exchange rate.  But the interest parity condition implies that (with lower interest rates) the exchange rate is expected to appreciate relative to the alternative currency.   With Dornbusch overshooting the currency still depreciates in the long run; the Keynesian effect outweighs the Fisherian effect. But that need not be true in all cases.

In January 2015, Switzerland simultaneously appreciated its currency sharply, and dramatically cut interest rates.  The effect was a policy that was contractionary in both the Keynesian and Fisherian sense.  The Swiss franc immediately appreciated sharply, and was expected to continue appreciating over time (due to the low rates).  In a few cases, exactly the opposite occurs, usually in developing countries experiencing a crisis.  Thus places like Argentina or Indonesia might see their currency sharply depreciate in a crisis, and also see a huge rise in interest rates—which is a forecast of further depreciation (according to the interest parity condition.)  BTW, the interest parity condition does not hold perfectly true in the real world, but that’s not important for the points I’m making.  No macro model holds perfectly true—it’s a model, a stylized picture of reality.

When the US announced the QE of March 2009, the dollar plunged sharply and interest rates fell.  That was an example of Dornbusch overshooting, Keynesian monetary stimulus dominating Fisherian monetary contraction.  By “dominating”, I mean that in the long run the exchange rate ends up lower than before the shock, despite appreciating after the original overshoot lower.  It was easier money, in net terms.

Now let’s imagine the X/Y policy graph I described as a vast plain, with economists living on that featureless surface.  Some economists are only able to see things along the X-axis direction.  We’ll call these economists “Keynesians”.  They think lower interest rates represent easier money.  Others only see things along the Y-axis.  We’ll call these economists “NeoFisherians.”  They believe lower interest rates represent tighter money.   Others can see in two dimensions, we’ll call them “monetarists”.  They do not believe that interest rates tell us anything useful about the stance of monetary policy.

Comments and suggestions are welcomed.

PS.  I’d rather not use money or exchange rates as a monetary indicator, rather I’d prefer to rely on NGDP futures prices.  The level/growth rate distinction also applies there, but is complicated by the fact that NGDP responds slowly to shocks.  Thus unlike with exchange rates, “level shifts” actually take a bit of time.  Recall mid-2008 to mid-2009, which was a sort of level shift down in NGDP, of roughly 8% below trend.  Then the growth rate going forward also fell by about 1%, from 5% to 4%.

Every day it gets worse

Little did we know that during the golden 1990s we were complaining about things that would look utterly trivial in retrospect. The sheer stupidity of the 21st century is so mind-boggling it leaves me almost speechless.

But not quite.

Consider the “problem” of currency manipulation. Let’s start with the fact that currency manipulation is a strange term to apply to a hodgepodge of government policies that may or may not impact the current account balance. For instance, you might say that “currency manipulation” is almost the sole purpose of having a central bank.

There are some smarter economists who do worry about currency manipulation. But when you read their work, it’s pretty clear that what actually concerns them is “saving manipulation”—when countries enact policies that boost the national saving rate. These policies can “improve” the current account balance. And not all such policies, rather they worry most about a subset of relatively ineffective policies, such as swapping domestic assets for foreign assets. (I’m not saying these policies have no effect; I just don’t see how it could be very large.)  They tend not to worry as much about far more effective pro-saving policies, in the fiscal/tax area.

The Netherlands and Switzerland have CA surpluses of 10% of GDP, while Singapore’s is 20% of GDP.  Does anyone seriously believe those are due to “currency manipulation”?

Even the economists who do worry about currency manipulation find the criteria set by the US government to be absurd:

Congress’s criteria to assess if a country is interfering in its currency are: A minimum $20 billion trade surplus with the U.S., a current account surplus in excess of 3 percent of gross domestic product, and repeated intervention in currency markets.

I’ve got an idea!  Instead of labeling countries “currency manipulators” when they accumulate $20 billion surpluses with the US, how about labeling then “currency manipulators” when they, umm, manipulate their currencies?

I’ll tell you why not.  Because that would force us to actually define currency manipulation in a way that could be measured.  And that would expose the fact that what really concerns us is saving manipulation.  No, not even saving manipulation, it’s current account surpluses in other countries that actually concern us.  No, not even that, it’s bilateral deficits with other countries that concern us.  And of course bilateral deficits have nothing to do with currency manipulation in any meaningful sense of the term. Indeed they have nothing to do with anything meaningful at all.   What’s the bilateral trade deficit between New York and New Jersey?

Trump took office saying he would label China a currency manipulator from day one.  He’s failed to deliver on that promise, just as he’s failed to repeal Obamacare, secure the border, reduce the trade deficit, or stop the rest of the world from laughing at us.  He failed because the Trump’s own Treasury department wasn’t able to find evidence that China is a currency manipulator, despite using a silly set of criteria that are strongly biased toward finding China guilty, such as the provision that it’s not OK to run a $20 bilateral surplus with the US.

But it’s even worse.  Not satisfied with the fact that the Treasury’s own criteria show that China is not a currency manipulator, they are thinking of changing the criteria so that the evidence will match the predetermined verdict—guilty as charged:

Treasury Secretary Steven Mnuchin is open to changing how the U.S. determines which nations are gaming their currencies, a move that could give President Donald Trump the chance to officially brand China a foreign exchange-rate manipulator as he seeks leverage to redefine trade terms between the world’s largest economies.

One method Mnuchin would consider: Using a 1988 trade act with a broad definition of currency manipulation to designate a country a manipulator, even if the label isn’t warranted by specific tests under a 2015 law, he said. The other would be to change the criteria that help establish whether a country is engaging in competitive devaluation of its currency, according to Mnuchin.

Treasury applies three tests to measure whether a country should be labeled a currency manipulator. The framework of the criteria is provided by Congress, but the specific thresholds in the tests are at Treasury’s discretion.

Again, foreign current account surpluses are not a problem for the US.  But if you disagree with me and agree with those pundits who do worry about current account imbalances, you should be focusing on the Eurozone and Japan and Switzerland, which really do have big CA surpluses, not China, whose CA is nearly balanced.

Trump seems determined to launch a cold war against China, a country with an economy that will be twice as large as the US economy by 2035.  In the old days, militaristic countries would engage in warfare by inventing some silly pretext—say demanding that a smaller neighboring country apologize for some imagined slight.  Trump wants a cold war with China, and demands the federal bureaucracy find some sort of fig leaf to justify it.  Why not point to China’s bad human rights record in Xinjiang?  Unfortunately, mentioning human rights would simply highlight Trump’s embarrassingly friendly relationship with the Russians and the Saudis, despite their war crimes in the Ukraine and Yemen.  So Trump needs to seek out an economic rationale for war with China.  In this post-truth world, currency manipulation is as good as any.

Two examples of low interest rate monetary policies

I’ve done a number of posts comparing New Keynesian and NeoFisherian views on the relationship between monetary policy and interest rates.  Here I’d like to illustrate the problem with a picture, as people often have trouble understanding this issue.  It’s really hard to not reason from a price change.  It’s hard to stop thinking of interest rate movements as a “policy” rather than an outcome.

These two graphs show the path of the exchange rate (E) over time, under two different monetary policies.  In both cases a higher exchange rate (E rising) reflects domestic currency appreciation.  Importantly, both of these examples are “low interest rate policies”, when the central bank reduces interest rates to a lower level than before.  But case #1 is an easy money policy, whereas case #2 is a tight money policy:

Screen Shot 2018-05-26 at 4.51.28 PM

To focus on the essentials, I’d like to assume that a policy change occurs at time = T’, and that the following movement in the exchange rate is anticipated, once policy has shifted.  (The policy move itself was unanticipated beforehand.)

Notice that in both cases, the exchange rate is expected to appreciate after time = T’.  Because of the interest parity theory, this expected appreciation means that interest rates will be lower than before the policy change, when the exchange rate was stable and interest rates were the same as in the other country.  So from the interest parity theory we know that these two cases are both shifts to a lower interest rate policy.

But now let’s look at the long run impact of the two policies on the level of the exchange rate.  In case #1, the exchange rate ends up lower (depreciated) in the long run, despite the near-term expectation of appreciation.  Because of PPP, that means the policy is expected to increase the price level in the long run.  In other words, it’s an expansionary monetary policy.

In case #2, the exchange rate appreciates in the long run, yielding a lower price level.  That’s a contractionary policy.

Because the first case looks so convoluted—a currency that is expected to appreciate over time but still end up lower than before—you might think it represents the “weird and controversial model”.  Just the opposite, the first case is the New Keynesian model of easy money, and more specifically the Dornbusch overshooting version.  The second more straightforward case reflects the weird and controversial NeoFisherian model.  Just looking at the second graph, it’s easy to see how the NeoFisherians are able to get their result from mainstream mathematical models of the economy.

Here’s another way of thinking about the two cases.  In case #1, there is a one-time increase in the money supply (and/or reduction in money demand).  It reduces interest rates (due to the liquidity effect.)  But it also leads to expectations of a higher price level in the long run, due to currency depreciation and PPP.  Because prices are sticky in the short run, the effect of easy money is to initially depreciate the currency, not raise the price level in proportion.

In case #2, there is a permanent decrease in the growth rate of the money supply (and/or increase in money demand growth).  Because of the quantity theory of money, that leads to a permanent decrease in the inflation rate.  And because of the Fisher effect, the lower inflation leads to lower nominal interest rates.  And because of interest parity, lower nominal interest rates lead to an expected appreciation in the currency.  But you don’t even need the interest parity relationship.  By itself, the lower expected inflation combined with PPP leads to the expected appreciation in the currency.

So how does this help us to better understand the New Keynesian/NeoFisherian dispute?  It may be helpful to contrast the “highly visible” with the “highly important”.  The New Keynesians are focused on the highly visible, while the NeoFisherians are focused on the highly important.

The vast majority of specific, short-term decisions by central banks are better viewed as one-time shifts in the money supply, rather than permanent changes in the growth rate of the money supply.  Thus “easy money” announcements often make short-term interest rates fall, even as inflation expectations rise.  At the same time, the truly major moves in interest rates over time largely reflect longer-term changes in the growth rate of the money supply (and money demand—in more recent years).  Thus the low nominal rates in Japan are primarily due to tight money, not easy money.

Both the New Keynesian and the NeoFisherian models are wrong, as both sides engage in reasoning from a price change.  The correct (market monetarist) model says that low rates can reflect easy or tight money, and that one should not draw any inferences about the current stance of monetary policy by looking at interest rates.

If one cannot draw any inferences about the current stance of policy by looking at rates, can one draw any inferences at all?  I see two:

1.  On any given day, a decision by a central bank to cut rates by more than the market expected is usually (not always) expansionary.  It reflects “expansionary intent” and may be viewed as a signal by the central bank of a desire to make policy more expansionary.  This is, of course, consistent with New Keynesianism.  But it does not mean the current stance of policy is expansionary.

2.  When nominal interest rates fall persistently over a long period of time, it is usually (not always) evidence that monetary policy has been contractionary.  (This is more consistent with NeoFisherism).  But it does not mean that the current stance of monetary policy is contractionary.  As usual, Milton Friedman was decades ahead of the rest of the profession:

Low interest rates are generally a sign that money has been tight, as in Japan; high interest rates, that money has been easy.  .  .   .

After the U.S. experience during the Great Depression, and after inflation and rising interest rates in the 1970s and disinflation and falling interest rates in the 1980s, I thought the fallacy of identifying tight money with high interest rates and easy money with low interest rates was dead. Apparently, old fallacies never die.

In America, monetary policy in 2017 and 2018 became a bit more expansionary, despite higher rates.

Where the FTPL applies

The fiscal theory of the price level does not explain very much in the US.  Inflation often soars much higher during periods when the national debt is low and falling (the 1960s) and falls sharply when the deficit increases dramatically (the 1980s).  But the FTPL does explain the inflation dynamics of Argentina:

“The [peso] price action looks like a loss of confidence by foreign investors coupled with some form of “capitulation” by domestic investors,” he added. “Markets need to see a radical tightening in fiscal policy in order to stabilise the situation, and that includes cutting wage hikes in order to fight inflation.

There is also some data that sounds suspiciously NeoFisherian:

Argentina’s peso is again feeling the heat.

The currency has fallen to a new record low of 23 against the dollar after slumping 5 per cent in morning trade on Tuesday. . . .

The declines come despite massive intervention by the Argentine central bank, which hiked interest rates by an unprecedented 12.75 percentage points to 40 per cent in the space of just seven days last week.

As always, however, you need to keep in mind the correlation/causation distinction.  Most likely it’s the high inflation causing the high nominal interest rates, not vice versa.  (Or if you prefer, the budget deficits are causing both.)

Money is fundamental, interest rates are secondary

Let’s try one more time, with the dollar/yen forward exchange rate.  I’d like to make the following assumptions.  It doesn’t matter whether you think these assumptions describe the real world; I’d simply like you to consider them as a hypothetical.  When we’re all done, we’ll think about what it means.

1.  Let’s assume the BOJ is determined to adopt a very tight money policy, over the next 30 years.  This policy will be so tight that the yen will end up valued at 50 to the dollar, more than double its current value.

2.  This very tight money policy causes very low inflation and very low NGDP growth in Japan.

So far interest rates don’t enter the picture, indeed interest rates need not even exist—imagine a world with no debt. I’m trying to make the appreciation of the yen into the fundamental shock, from which everything else flows.

3.  Now let’s add interest rates.  Because of the ultra-low expected inflation, and the ultra-low expected NGDP growth, nominal interest rates in Japan are more than 200 basis points below nominal interest rates in the US.  These low rates are caused by a tight money policy that leads to yen appreciation.

I’m still assuming the tight yen policy that leads to yen appreciation is fundamental, and everything else is an effect of that policy.

4.  Now let’s assume that the US and Japanese debt markets are very deep and liquid, and the 30-year forward yen contract is very lightly traded and not very liquid at all.  Let’s also assume that the forward premium on the yen is linked to the interest rate differential according to the covered interest parity theorem, although the theorem doesn’t work perfectly due to various market imperfections caused by regulations.  It’s roughly true.

I’m still assuming the tight yen policy that leads to yen appreciation is fundamental, and everything else is an effect of that policy.

Now let’s take stock of where were are.  Thus far, I have NOT claimed to describe the real world.  I’ve described a scenario where, by assumption, the huge forward premium on the yen drives the interest rate differential.  Quite possibly, this imaginary scenario has nothing to do with the real world.

But here’s the problem.  Not one commenter has given me a single fact that would lead me to conclude that this imaginary scenario does not in fact describe the real world.  Note, for instance, that I assumed that the two bond markets are highly liquid and traders focus on the interest rate spread.  I assumed the forward yen is lightly traded, and hence considered peripheral in the world of finance.  But I’ve also constructed an example where, by assumption, that difference in liquidity between the two markets has no bearing on causality.

So what would count as evidence against my imaginary scenario?  Perhaps you could convince me that while the 30-year forward yen is 50, traders actually expect the yen to be trading at 105 in the year 2048.  And investors continue to buy low yield JGBs in any case, because of market segmentation, or some other reason.  So the differences in interest rates are unrelated to differences in inflation, etc. If you offered that sort of explanation, and backed it up with evidence, I would be persuaded.  But I’m not seeing people do that.  Until then, I’m going to assume the causality goes from an appreciating yen to a situation where Japanese interest rates are lower than American interest rates.

PS.  The “carry trade” may partly explain why people disagree with me, but carry trades suffer from the “peso problem”, so I’m not convinced the carry trade will “work” going forward.  If Japanese inflation stays well below US inflation (as I expect), then the carry trade will break down at some point.

PPS.  Financial variables may or may not be linked to macro events.  The 1929 stock market crash seems to have been linked to fears of depression, while the 1987 stock market crash seems to have been sort of random.  You can view my claim here as being that the 1929 case is more typical.  Asset prices move based on shifting expectations regarding economic fundamentals.  Even if a forward exchange rate market did not exist, I’d claim that expectations of the future spot rate drive the interest rate differential.