In such a world, by adjusting the level of the federal funds rate, the FOMC could be fully confident that it could generate the appropriate financial conditions necessary to support achievement of full employment and price stability. In fact, the response of financial conditions to changes in short-term interest rates is not rigid and predictable. Instead, as we shall see shortly, the linkage between the federal funds rate and financial conditions changes over time, as it is influenced by a whole host of other factors. Recent evidence suggests that even the relation between short-term and long-term rates has shifted substantially over the past 15 years.4 Moreover, at times, we have observed cases in which financial conditions did not move in the same direction as the monetary policy stance. Let me highlight two recent divergences which indicate that we need to keep a separate eye on the evolution of financial conditions. The first occurred in the mid-2000s. In June 2004, the FOMC decided to begin raising the federal funds rate target in order to remove policy accommodation. It raised the target in 25-basis-point increments at 17 consecutive meetings, pushing the rate up from a starting point of 1.0 percent to a peak of 5.25 percent. Despite this tightening of monetary policy over two years, financial conditions failed to tighten in a similar manner. This can be seen by looking at the behavior of well-known measures of financial conditions during this period (Exhibit 1).
Accordingly, we should care much more about longer-term movements in financial conditions than about higher-frequency, transitory movements. That is because behavior in firms and households will be influenced much more by how financial conditions evolve over time, rather than by where they happen to be at a particular moment. To emphasize this point, let me give two contrasting examples—one where financial conditions moved sharply but not persistently, and another where financial conditions moved systematically over a longer time period. We will see that it is the long-lived movements that have the largest influence on the economic outlook. For the first example, consider the U.S. equity market in 1987. The S&P 500 index began the year at 242, shot up to a peak of 337 in August (an increase of almost 40 percent) and plummeted to a trough of 225 in October (a fall of 33 percent). When the stock market fell more than 20 percent on October 19th—which came to be known as “Black Monday”—many feared that the decline would lead to a recession. After all, that crash was the largest-ever one-day percentage decline of the U.S. stock market. But, no recession occurred. Importantly, households sustained their spending despite the sharp decline in household wealth. This happened, in part, because household spending had not yet responded much to the sharp run-up in stock prices earlier in the year, so consumer spending turned out to be relatively insensitive to the market’s sharp reversal.