The idea that monetary policy should be conducted in a systematic and predictable way is not new. One of the earliest, and most controversial, proposals was Milton Friedman’s famous k-percent money growth rule.2 Friedman argued that monetary policy was a major contributor to cyclical fluctuations. He argued that efforts by the central bank to “stabilize” or “fine-tune” the real economy were fraught with danger because we didn’t know enough about the short-run dynamics of monetary actions to reliably predict their effects on the real economy. As a result, monetary policy ended up being a source of real instability rather than a stabilizing influence.
In addition, Friedman correctly argued that sustained inflation was always a monetary phenomenon and that in a world of paper or fiat money, the central bank had the obligation to preserve money’s purchasing power so that markets would not be distorted by inflation. Price stability would therefore promote a more efficient allocation of resources. At the time, this view of the importance of price stability was controversial, but today it is widely accepted.
Thus, Friedman highlighted two central features of good monetary policy that are hallmarks of the rules that I will turn to shortly. First, he argued that monetary policy should be formulated in a way that stabilized the purchasing power of money. Second, he stressed monetary policy should not be used to “fine-tune” real economic activity because attempting to do so often introduced instability into the real economy instead of improving economic performance. His actual proposal was that the Federal Reserve should announce that the money supply would be allowed to grow at k-percent a year -- period. With k a suitably low number, such a policy rule would ensure that inflation would never become a problem and that monetary policy would cease to be an independent source of cyclical fluctuations.
The Friedman rule is simple and easy to communicate. It also gives a high degree of predictability to monetary policy. Had it been implemented, it surely would have prevented the double-digit inflation the U.S. economy suffered in the late 1970s, as well as much of the subsequent economic disruptions in the early 1980s that occurred as inflation was brought back down to acceptable levels.
Yet the rule has several shortcomings that have limited its appeal. Most important, many economists view money demand as volatile, so that a constant supply of money could lead to more variability in inflation, and perhaps output, than necessary. Thus, most economists believe that some sort of policy that responds to the state of the economy could perform better.