Has the inflation process changed?

Inflation has been low in many countries for at least a decade. But have inflation processes changed in ways that would help make low inflation permanent? Using both aggregate and disaggregated inflation data, we find that the means of inflation processes have become smaller over the past two decades and that, allowing for these changes in the mean, their persistence has not declined much. Changes in monetary policy frameworks and recessions appear to have contributed to a reduction in the mean of inflation, but do not appear to have a meaningful impact on persistence, and there is some evidence that the shifts in inflation expectations are the proximate cause of the changes in the mean of inflation. These findings suggest that policy-makers should focus on maintaining credibility and carefully monitoring inflation expectations for any indication that they are rising.