A Note to Ryan Avent, Paul Krugman, and Arnold Kling

Do not underestimate the impact of the Fed's low interest rate policies in the early-to-mid 2000s. While there are many stories told as to how the low federal funds rate at this time contributed to the housing boom, one that is often overlooked but probably the most important is the "risk-taking" channel story of monetary policy. Leonardo Gambacorta of the BIS summarizes how this link works:

Monetary policy may influence banks’ perceptions of, and attitude towards, risk in at least two ways: (i) through a search for yield process, especially in the case of nominal return targets; and (ii) by means of the impact of interest rates on valuations, incomes and cash flows, which in turn can modify how banks measure risk.

Tobias Adrian and Hyun Song Shin also explore this channel in their paper:

We explore the hypothesis that financial intermediaries drive the business cycle by way of their role in determining the price of risk. In this framework, balance sheet quantities emerge as a key indicator of risk appetite and hence of the “risk-taking channel” of monetary policy. We document evidence that the balance sheets of financial intermediaries reflect the transmission of monetary policy through capital market conditions. We find short-term interest rates to be important in influencing the size of financial intermediary balance sheets.

Both papers above empirically show the low federal funds rates were very important to the excessive leverage and big bets made by financial institutions during this time. Barry Ritholtz provides a nice summary of this channel in a recent post:

What Bernanake seems to be overlooking in his exoneration of ultra-low rates was the impact they had on the world’s Bond managers — especially pension funds, large trusts and foundations. Subsequently, there was an enormous cascading effect of 1% Fed Funds rate on the demand for higher yielding instruments, like securitized mortgages...

An honest assessment of the crisis’ causation (and timeline) would look something like the following:

1. Ultra low interest rates led to a scramble for yield by fund managers;

2. Not coincidentally, there was a massive push into subprime lending by unregulated NONBANKS who existed solely to sell these mortgages to securitizers;

3. Since they were writing mortgages for resale (and held them only briefly) these non-bank lenders collapsed their lending standards; this allowed them to write many more mortgages;

4. These poorly underwritten loans — essentially junk paper — was sold to Wall Street for securitization in huge numbers.

5. Massive ratings fraud of these securities by Fitch, Moody’s and S&P led to a rating of this junk as TripleAAA.

6. That investment grade rating of junk paper allowed those scrambling bond managers (see #1) to purchase higher yield paper that they would not otherwise have been able to.

7. Increased leverage of investment houses allowed a huge securitization manufacturing process; Some iBanks also purchased this paper in enormous numbers;

8. More leverage took place in the shadow derivatives market. That allowed firms like AIG to write $3 trillion in derivative exposure, much of it in mortgage and credit related areas.

9. Compensation packages in the financial sector were asymmetrical, where employees had huge upside but shareholders (and eventually taxpayers) had huge downside. This (logically) led to increasingly aggressive and risky activity.

10. Once home prices began to fall, all of the above fell apart.

[...]

Inadequate regulations and “nonfeasance” in enforcing existing regs were, as Chairman Bernanke asserts, a major factor. But in the crisis timeline, the regulatory and supervisory failures came about AFTER the 1% Fed rates had set off a mad scramble for yields. Had rates stayed within historical norms, the demand for higher yielding products would not have existed — at least not nearly as massively as it did with 1% rates.

Now Ritholtz acknowledges there were many factors at work during this boom. However, he makes the point, and I agree, that we have failed to learn a key lessons from this crisis if we move forward with the view that the low interest rates were of no consequence during the housing boom.