So the Fed decided not to raise rates this weeks. And as you’ve probably seen, this provoked an angry response from representatives of financial institutions. The owners and managers of money have been demanding higher interest rates for years now, and were clearly hoping that this week they’d finally start getting them.
As Paul Krugman points out, it’s not immediately obvious why money-owners are so hostile to low rates:
I’ve tried to understand demands that rates go up despite the absence of inflation pressure in terms of broad class interests. And the trouble is that it’s not at all clear where these interests lie. The wealthy get a lot of interest income, which means that they are hurt by low rates; but they also own a lot of assets, whose prices go up when monetary policy is easy. You can try to figure out the net effect, but what matters for the politics is perception, and that’s surely murky.
But, he has a theory:
What we should be doing … is focusing not on broad classes but on very specific business interests. … Commercial bankers really dislike a very low interest rate environment, because it’s hard for them to make profits: there’s a lower bound on the interest rates they can offer, and if lending rates are low that compresses their spread. So bankers keep demanding higher rates, and inventing stories about why that would make sense despite low inflation.
I certainly agree with Krugman that in thinking about the politics of monetary policy, we should pay attention to the narrow sectoral interests of the banks as well as the broader interests of the owning class. But I’m not sure this particular story makes sense. What he’s suggesting is that the interest rate on bank lending is more strongly affected by monetary policy than is the interest rate on bank liabilities, so that bank spreads are systematically wider at high rates than at low ones.
This story might have made sense in the 1950s and 1960s, when bank liabilities consisted mostly of transactions deposits that paid no interest. But today, non-interest bearing deposits compose less than a quarter of commercial bank liabilities. Meanwhile, bank liabilities are much shorter-term than their assets (that’s sort of what it means to be a bank) so the interest rates on their remaining liabilities tend to move more closely with the policy rate than the interest rates on their assets. So it’s not at all obvious that bank spreads should be narrower when rates are low; if anything, we might expect them to be wider.
Luckily, this is a question we can address with data. Historically, have higher interest rates been associated with a wider spread for commercial banks, or a narrower one? Or have interest rate changes left bank spreads unchanged? To answer this, I looked at total interest income and total interest payments for commercial banks, both normalized by total assets. These are reported in a convenient form, along with lots of other data on commercial banks, in the FDIC’s Historical Statistics on Banking.
The first figure here shows annual interest payments and interest costs for commercial banks on the vertical axis, and the Federal funds rate on the horizontal axis. It’s annual data, 1955 through 2014. The gap between the blue and red points is a measure of the profitability of bank loans that year.  The blue and red lines are OLS regression lines.
If Krugman’s theory were correct, the gap between the blue and red lines should be wider on the right, when interest rates are high, and narrower on the left, when they’re low. But in fact, the lines are almost exactly parallel. The gap between banks’ interest earnings and their funding costs is always close to 3 percent of assets, whether the overall level of rates is high or low. The theory that bank lending is systematically less profitable in a low-interest environment does not seem consistent with the historical evidence. So it’s not obvious why commercial banks should care about the overall level of interest rates one way or the other.
Here’s another way of looking at the same thing. Now we have interest received by commercial banks on the vertical axis, and interest paid on the horizontal axis. Again, both are scaled by total bank assets. To keep it legible, I’ve limited it to the years 1985-2014; anyway the earlier years are probably less relevant for today’s banking system. The diagonal line shows the average spread between the lending rate and the funding rate for this period. So points above the line are years when bank loans are unusually profitable, and points below are years when loans are less profitable than usual.
Here again, we see that there is no systematic relationship between the level of interest rates and the profitability of bank loans. Over the whole range of interest rates, spreads are clustered close to the diagonal. What we do see, though, is that the recent period of low interest rates has seen a steady narrowing of bank spreads. Since 2010, the average interest rate received by commercial banks has fallen by one full percentage point, while their average funding cost has fallen by a bit under half a point.
On the face of it, this might seem to support Krugman’s theory. But I don’t think it’s actually telling us anything about the effects of low interest rates as such. Rather, it reflects the fact that bank borrowing is much shorter term than bank lending. So a sustained fall in interest rates will always first widen bank spreads, and then narrow them again as lending rates catch up with funding costs. And in fact, the recent decline in bank spreads has simply brought them back to where they were in 2007. (Or in 1967, for that matter.) No doubt there are still a few long-term loans from the high-rate period that have not been refinanced and are still sitting profitably on banks’ books; but after seven years of ZIRP there can’t be very many. There’s no reason to think that continued low rates will continue to narrow bank spreads, or that higher rates will improve them. On the contrary, an increase in rates would almost certainly reduce lending profits initially, since banks’ funding rates will rise more quickly than their lending rates.
Now, on both substantive and statistical grounds, we might prefer to look at changes rather than levels. So the next two figures are the same as the previous ones, but using the year over year change rather than absolute level of interest rates. In the first graph, years with the blue above the red are years of widening spreads, while red above blue indicates narrowing spreads. In the second graph, the diagonal line indicates an equal change in bank lending and funding rates; points above the line are years of widening spreads, and points below the line are years of narrowing spreads. Again, I’ve limited it to 1985-2014.
Both figures show that rising rates are associated with narrower commercial bank spreads — that is, less profitable loans, not more profitable. (Note the steeper slope of the red line than the blue one in Figure 3.) Again, this is not surprising — since banks borrow short and lend long, their average funding costs change more quickly than their average lending rates do. The most recent three tightening episodes were all associated with narrower spreads, not wider ones. Over 2004-2006, banks’ funding costs rose by 1.5 points while the average rate on their loans rose by only 1.3 points. In 1999-2000, funding costs rose by 0.55 points while loan rates rose by 0.45 points. And in 1994-1996, bank funding costs rose by 0.6 points while loan rates rose by 0.4 points. Conversely, during the period of falling rates in 2007-2008, bank funding costs fell by 1.7 points while average loan rates fell by only 1.4 points. Admittedly, these are all rather small changes — what is most striking about banking spreads is their stability. But the important thing is that past tightening episodes have consistently reduced the lending profits of commercial banks. Not increased them.
Thinking about the political economy of support for higher rates, as Krugman is doing, is asking the right question. And the idea that the narrow interests of commercial banks could be important here, is reasonable on its face. But the idea that higher rates are associated with higher lending spreads, just doesn’t seem to be supported by the data. Unfortunately, I don’t have a simple alternative story. As the late Bob Fitch used to say, 90 percent of what happens in the world can be explained by vulgar Marxism. But banks’ support for hard money may fall in the other 10 percent.
UPDATE: For what it’s worth, here are the results of regressions of average interest received by commercial banks and of and their average funding costs, on the Federal Funds rate. Both interest flows are normalized by total assets.
|Full Period (1955-2014)||1955-1984||1985-2014|
Again, we don’t see any support for the hypothesis that spreads systematically rise with interest rates. Depending on the period and on whether you look at levels or changes, you can see a slightly stronger relationship of the Federal Funds rate with either bank lending rates of funding costs; but none of these differences would pass a standard significance test.
Two positive conclusions come out of this. First, all the coefficients are substantially, and significantly, below 1. In other words, the policy rate is passed through far from completely to market rates, even in the interbank market, which should be most closely linked to it. Second, looking at the bottom half of the table, we see that changes in the policy rate have a stronger affect on both the funding and lending rates (at least over a horizon of a year) today than they did in the postwar decades. This is not surprising, given the facts that non-interest-bearing deposits provided most bnk funding in the earlier period, and that monetary policy then worked through more limits on the quantity of credit than interest rates per se. But it’s interesting to see it so clearly in the data.
UPDATE 2: Krugman seems to be doubling down on the bank spreads theory. I hope he looks a bit at the historical data before committing too hard to this story.
VERY LATE UPDATE: In the table above, the first set of rows is levels; the second is year-over-year changes.
 This measure is not quite the same as the spread — for that, we would want to divide bank interest costs by their liabilities, or their interest-bearing liabilities, rather than their assets. But this measure, rather than the spread in the strict sense, is what’s relevant for the question we’re interested in, the effect of rate changes on bank lending profits. Insofar as bank loans are funded with equity, lending will become more profitable as rates rise, even if the spread is unchanged. For this reason, I refer to banks average funding costs, rather than average borrowing costs.