The Federal Reserve building in Washington. 

The Federal Reserve building in Washington.  Credit: AP/Patrick Semansky

The Federal Reserve's pitched battle with rising prices has given rise to widespread concerns about a possible return of stagflation - the combination of high unemployment and high inflation that afflicted the U.S. in the 1970s.

Actually, a bit of stagflation is just what the Fed should be - and appears to be - aiming for.

Monetary policy acts with a lag: If a central bank wants inflation to be lower a couple years in the future, it must raise interest rates now, to generate the slack in consumer and labor demand needed to slow growth in prices and wages. The appropriateness of its policy should thus be judged on where it expects unemployment and inflation to be. It shouldn't, for example, plan to miss its targets in opposite directions - a policy rule known as Qvigstad's criterion (after the Norwegian central banker Jan Qvigstad). If unemployment remains elevated when inflation is already below target, monetary policy has been too tight, inflicting more economic pain than necessary.

Logical as this all might be, it has a perhaps surprising implication: If the Fed is doing its job right, it will push up the unemployment rate before inflation declines, and both will remain elevated until they reach their targets. In other words, in accordance with what Qvigstad recommends, the Fed should be seeking to achieve a period of stagflation.

Judging from the Fed's most recent economic projections, a small amount of stagflation is exactly what it's going for. The median forecast, which assumes appropriate monetary policy, puts inflation and unemployment about 0.3 and 0.4 percentage point above target, respectively, at the end of 2024. While Qvigstad's criterion offers no guidance on what the relative size of unemployment and inflation misses should be, it appears that the Fed views a roughly one-for-one trade-off as appropriate.

Granted, the Fed's forecasts tell us nothing about how it might respond if the economic outlook worsens. If, for example, officials decide that supply disruptions will be more persistent than previously thought, will they stick to the one-for-one tradeoff - allowing, say, inflation and unemployment to pass through 5% and 7% on their way to their targets? How much stagflation is the central bank willing to tolerate? This is a crucial policy question that the Fed needs to answer publicly.

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners. Narayana Kocherlakota is a Bloomberg Opinion columnist. He is a professor of economics at the University of Rochester and was president of the Federal Reserve Bank of Minneapolis from 2009 to 2015.