The article examines long-term trends in commodity prices from 1900 to 1992. By analyzing 24 of the most-traded commodities, the researchers found that 15 showed decreasing prices, six had stable prices, and three had increasing prices. This supports the idea proposed by Prebisch and Singer in 1950 that commodity prices generally decline over time. Additionally, the study revealed that the persistence of price shocks in commodities is lower than previously thought, suggesting there is room for stabilization and support mechanisms for most commodities.