US: Agricultural productivity up, real price of outputs down
Transitory events—such as energy shocks or supply shortages due to bad weather—may cause agricultural commodity prices to rise, the long-term growth trend in U.S. agricultural productivity has enhanced food security and benefited consumers by reducing the real (inflation-adjusted) price of agricultural outputs over time. Between 1948 and 2015, total factor productivity increased by 152 percent, while real agricultural output price declined by nearly 65 percent.
This chart appears in the March 2018 Amber Waves data feature, "Agricultural Productivity Growth in the United States: 1948-2015."