Fertilizer consumption by the U.S. agricultural sector has increased dramatically for several decades. Nitrogen fertilizer use increased 632 percent between 1952 and 1976. Phosphate and potash fertilizer use increased 138 and 229 percent, respectively, in the same period (USDA 1978). However, the upward trend in fertilizer use was temporarily interrupted during the early and mid-1970s as the real fertilizer price began to increase after many years of decline.
Higher levels of aggregate fertilizer consumption over the 1952–1976 period outweighed the decline in the real price of fertilizer as real dollar expenditures for fertilizer continued to rise. Our study includes an attempt to relate fertilizer use for different crops to relevant economic variables.