The Fed has a dual mandate, written into law, from Congress: maintain stable prices and achieve maximum employment. The graph above shows the track record for the first part of the mandate, which is what we focus on here. Now, the interpretation of what “stable prices” means has changed over time, but the Fed’s current inflation target is about 2%. And, indeed, it looks like the Fed has done a pretty good job since the 1980s compared with previous periods. What about before that?

First, the Fed didn’t exist until 1913; and the pre-Fed period had wild swings in the inflation rate, as well as long periods of deflation, which some consider very problematic. Between the world wars, inflation was quite erratic, too, with some bouts of deflation. But Fed policy wasn’t driven by an inflation mandate at that time, but rather by a gold standard. From World War II up until the 1970s, the U.S. had a couple of episodes of high inflation, but there was no inflation mandate then either. In fact, there was also quite a bit of federal government intervention in monetary policy. Obviously, this short list oversimplifies the history of inflation in the U.S., but it looks like having a clear objective may have helped the Fed focus on and achieve this particular metric.

How this graph was created: Start at the NBER’s Macrohistory Database. Select the index of the general price level and click “Add to Graph.” From the “Edit Graph” panel, use the “ADD LINE” option to search for and select CPI. Change units to “Percent Change from Year Ago,” and click “Copy to all.”

Suggested by Christian Zimmermann.