Monthly U.S. inflation from 1995 through 2019 is well explained by statistics summarizing the monthly distribution of relative price changes. We document this relationship and use it to evaluate the behavior of inflation during and after the COVID-19 pandemic. In earlier periods when inflation was not stable, the relationship between inflation and the distribution of relative price changes shifts, much like the Phillips curve. We use that shifting relationship to derive a measure of underlying inflation that complements existing measures used by central banks.
