Weekly Market Comment Archive
Investment Research & Insight Page
Sixteen Cents: Pushing the Unstable Limits of Monetary Policy John P. Hussman, Ph.D. All rights reserved and actively enforced. Reprint Policy
This week's comment focuses on the current, unstable stance of monetary policy. We'll start by reviewing some important monetary relationships. While I've included a variety of graphs and equations to support the analysis, I've boldfaced several key points, and my hope is that the text has enough detail that you can skip some of the equations if you're not a math fan.
One of the best known relationships in economics is the concept of "liquidity preference" - essentially money demand. Both theoretically and in actual data, there is a fairly tight relationship between short-term interest rates, and the amount of non-interest-bearing money that people are willing to hold, either directly as currency, or indirectly as bank reserves. Basically, the lower interest rates are, the more cash or reserves ("base money") people are willing to carry around, per dollar of nominal GDP. As interest rates move higher, people naturally respond to the opportunity to earn interest by reducing the amount of cash they carry, both directly and indirectly.
You can see this relationship in the chart below, which plots the 3-month Treasury bill yield versus liquidity preference for base money. Though "liquidity preference" is often used to describe the broad demand for money, we will define liquidity preference more specifically here as the amount of base money demanded per dollar of nominal GDP. In post-war data, the lower bound for liquidity preference has been roughly 5 cents of base money holdings for every dollar of nominal GDP. With interest rates nearly zero at present, people are directly and indirectly holding much larger amounts of base money, currently slightly more than 13 cents for every dollar of GDP. The cluster of points at the extreme right of the graph are recent data. In a panic to hold cash, liquidity preference hit 15 cents at the height of the 2009 credit crisis.
By comparison, Japanese liquidity preference has historically ranged from a low of about 0.08 to a high of nearly 0.12 when interest rates have been pressed toward zero.
The idea of monetary "velocity" seems slightly more theoretical, but velocity is simply the inverse of liquidity preference: it measures the amount of nominal GDP per dollar of monetary base. Not surprisingly, the chart of velocity is a mirror image of liquidity preference.
The exchange equation
OK. So we've established that there is a clear relationship between money demand and interest rates. As it happens, there's also a well-known relationship between money, velocity, output and prices, which is called the "exchange equation." The exchange equation is actually just a simple identity. Notice that nominal GDP is just real GDP ("Y") times the GDP price index ("P"). Velocity is equal to nominal GDP divided by the monetary base, so
V = PY/M
which is usually written
MV = PY
Although this is a simple identity, people like to tinker with one variable or another while incorrectly assuming that the other parts of the equation are simply constant. For example, people often assume that doubling the monetary base will simply double the price level, but that requires V and Y to stay constant, which is hardly an accurate assumption. Likewise, advocates of easy money seem to believe that increasing the money supply will buy you more economic output, but this requires holding V and P relatively constant.
If you look at the historical data, neither of these arguments hold a great deal of water. Rather, what seems to be true is that the strongest effect of an increase in the money supply is to drive short-term interest rates lower, thereby increasing liquidity preference (i.e. reducing velocity). So periods of very high growth in the monetary base are typically accompanied by nearly proportionate plunges in monetary velocity, without any strong effects on output or prices. As we'll see below, that isn't quite the whole story, but to a first approximation, the main effect of changes in the monetary base is to produce opposite and proportional changes in velocity.
From this perspective, there is little reason to expect the Fed's policy of "quantitative easing" to have real effects on economic output. Thus far, quantitative easing has had the effect of increasing idle bank reserves by about $62 billion since September, with a slight downward impact on Treasury bill yields. On a seasonally-adjusted basis, the monetary base has increased by about $36 billion since September, but since the seasonal adjustment factor plunges in the first two months of the year as holiday cash demands subside, the seasonally-adjusted monetary base will spike by about $60 billion even if the Fed does nothing in the next two months.
Of course, QE2 has had additional effects on the financial markets, but these have not been driven by monetary factors. Instead, they are rhetorical, based on the view that somehow the Fed's actions create a "backstop" that will prevent potential losses in risky assets. As Ambrose Evans-Pritchard has noted, "the Fed no longer even denies that the purpose of its latest blast of bond purchases, or QE2, is to drive up Wall Street, perhaps because it has so signally failed to achieve its other purpose of driving down borrowing costs." Unfortunately, it is easy to demonstrate that the greater the volatility of a security or income stream, the smaller the "wealth effect" that can be expected from a given increase in value. Volatile dollars have less impact on consumption than smooth dollars, which is why housing values have historically had a much greater wealth effect than stock market values.
Moreover, people clearly believe that the additional reserves are flowing wildly into risk assets, pushing prices higher as if secondary markets are some sort of balloon to be filled (one second of reflection will establish that every dollar that goes "into" a secondary market in the hands of a buyer comes back "out" of the secondary market in the hands of a seller). The fact, however, is that these reserves are sitting comfortably in the banking system as idle balances.
As a study by the Bank of Japan of its own huge experiment with QE concluded, "While we can enumerate several routes of the monetary base channel which suggest that expansion of the monetary base can have some expansionary effect on the economy, our analyses suggest that the quantitative magnitude of any such effect is highly uncertain and very small." [The Effect of the Increase in the Monetary Base on Japan's Economy at Zero Interest Rates - An Emprical Analysis, Bank of Japan, 2002].
In any event, it is clear that with regard to risky securities, the enthusiasm and rhetoric about QE2 has caused a reduction in the willingness of sellers to sell, and an increase in the eagerness of buyers to buy. That imbalance of eagerness between buyers and sellers has clearly affected prices of risky assets, but it does not generate new cash flows - it simply raises the valuation that the market places on existing streams of future cash flows, and thereby lowers the subsequent rate of return on holding those securities. I suspect this will end badly, but that's not the topic of this discussion.
Quantifying monetary policy
So let's review. Liquidity preference is simply the amount of monetary base that people are willing to hold, per dollar of nominal GDP. We've seen that this demand for base money is essentially a function of short-term interest rates. When interest rates are low, people are willing to hold higher cash balances. When interest rates are high, people tend to economize on cash balances.
Just a note - even if you hate math, it will help to skim the next few paragraphs, but feel free to skip to the next graph if you wish. After inverting velocity, taking logarithms, and doing other calculations that geeks find entertaining, it turns out that the liquidity preference function can be estimated fairly accurately. Using the 3-month Treasury bill ("i") alone, the relationship in post-war data is well described by:
M/PY = .094 - .022 * ln(i)
which gives you an implied equation for the 3-month Treasury bill yield as a function of liquidity preference:
i = exp(4.27 – 45.5*M/PY)
An even tighter relationship can be obtained by including the value of liquidity preference six months earlier:
M/PY = .0327 - .0077 * ln(i) + .65 * (M/PY)_lagged_6_mos
which again gives you an implied equation for the 3-month Treasury bill yield as a function of monetary variables:
i = exp(4.25 - 129.87*M/PY + 84.42*M/PY_lagged_6_mos)
The foregoing parameters are based on standard scaling factors used for reporting the variables, so GDP are and monetary base are in billions, and T-bill rates are in standard format. For example, given a current monetary base of $2,000 (billion) and nominal GDP of about $14,900 (billion), the expected 3-month Treasury bill yield here would be roughly exp(4.27-45.5*2000/14900) = 0.1592, which is about right (presently, the Treasury bill yield is 0.16%).
Let's take a quick look at the fit from these estimates. The chart below shows the actual velocity of the monetary base, along with estimated velocity. Notice that we've observed an enormous plunge in velocity over the past two years, which is fully consistent with the near-zero level of interest rates at present.
Of course, we can also invert this relationship. The chart below shows the actual level of the 3-month Treasury bill yield, along with the yield implied by monetary variables.
Pushing monetary policy to its unstable limits
But what about inflation? How is monetary policy related to prices?
Here is where things get really interesting. We've established that to a large extent, both liquidity preference and short-term interest rates respond fairly passively to changes in the monetary base. But of course, that's not the whole story. Not every change in interest rates or liquidity preference is passive, and when there is an exogenous "shock" to those factors - watch out.
Let's go back to the definition of liquidity preference (we'll call it "L").
L = M/PY
So
P = M/LY
It follows that we can impute the price level (GDP deflator) using base money, real GDP, and the level of liquidity preference implied by short-term interest rates.
With real GDP expected at about $13,409 billion in 2005 dollars for the fourth quarter of 2010, the implied GDP deflator is 2000/[(.094-.022*ln(.15))*13,409] = 1.10. The latest reading on the deflator was about 1.11, so the estimate is just about right.
The disturbing fact about this, however, is that inflation dynamics can potentially become unstable when a massive stock of base money is being kept in check by very low interest rates. This is because small increases in interest rates from near-zero levels imply huge changes in liquidity preference and velocity. If those changes are not offset by opposite and proportional changes in the monetary base, strong inflation pressures are likely to follow. Historically, it has usually taken an extended period of such inflation pressures (sustained over 6-12 months) before the implied inflation pressures are actually reflected in price levels. Temporary differences between the actual and implied GDP deflator are not very informative unless they are sustained.
Still, any sustained external pressure on short-term interest rates, even in the range of a quarter-percent or more, would require a rapid contraction in the Federal Reserve's balance sheet, or the upward pressure on velocity would create very strong incipient pressures on inflation.
For example, let's repeat the calculation for the implied GDP deflator, but assume a 3-month Treasury bill yield of 0.35%. In that case, holding the monetary base constant at its present level of $2 trillion, the implied deflator is 2000/[(.094-0.022*ln(0.35))*13,409] = 1.27. Compared with the 1.11 deflator implied by a 0.15% Treasury bill yield, the implied change in prices is about 14.4%.
Because the size of the monetary base has become so extreme relative to historical norms, the likely price pressures in response to even modestly higher short-term interest rates are equally extreme. For example, given the present level of the monetary base, an exogenous increase in short-term Treasury yields to even 1% would imply a GDP deflator of about 1.59, which is about 42.9% higher than present levels. In order to counter such pressure, the Fed would have to contract the monetary base by about $600 billion, from the present level of about $2 trillion to a still bloated but less extreme $1.4 trillion.
Read Full Article »