Time-series techniques that control for the presence of structural breaks reveal that the international price of most commodities presents a negative long-run trend for 1900-92. They also show that shocks are far less persistent than previously estimated. Both findings suggest that there may be...

In this paper we examine temporal properties of eleven natural resource real price series from 1870-1990 by employing a Lagrangian Multiplier unit root test that allows for two endogenously determined structural breaks with and without a quadratic trend. Contrary to previous research, we find...