From boom to bust: a typology of real commodity prices in the long run.

This paper considers the evidence on real commodity prices from 1900 to 2015 for 40 commodities, representing 8.72 trillion US dollars of production in 2011. In doing so, it suggests and documents a comprehensive typology of real commodity prices, comprising long-run trends, medium-run cycles, and short-run boom/bust episodes. The main findings can be summarized as follows: (1) real commodity prices have been on the rise—albeit modestly—from 1950; (2) there is a pattern—in both past and present—of commodity price cycles, entailing large and long-lived deviations from underlying trends; (3) these commodity price cycles are themselves punctuated by boom/bust episodes which are historically pervasive. [ABSTRACT FROM AUTHOR]