Exchange rates are now the single most important variable in determining the economic environment for agricultural trade. Currency values have important effects on the competitive position of the United States relative to other major agricultural exporters. Cycles of exchange rate swings since 1969 have coincided with changes in U.S. agricultural exports. Economic analysis indicates that the exchange rate accounted for more than 25 percent of the rebound in U.S. agricultural exports since 1985. While exchange rates are key to competitiveness of all agricultural exports, specific commodity markets show different levels of exchange rate variation. Wheat markets had the least movement, so currency values affected competitiveness of wheat exports the least, while soybean exchange rates changed markedly.