Fertilizer prices in the U.S. are driven by global and domestic factors. Growing demand for grain worldwide, both for human consumption and for animal feed, has led to the lowest level of grain stocks ever. This has forced grain prices higher, which in turn increased the demand for macronutrient fertilizers and especially nitrogen fertilizer. In addition to the traditional grain uses, biofuels made from commodity crops are further increasing demand for grains and therefore fertilizer. Most of this growth in agricultural production and fertilizer demand comes from developing countries, with Brazil, China, and India having the most impact. At the same time, nitrogen production in the U.S. has experienced a steep decline as a result of rapidly rising natural gas prices. Consequently, U.S. nitrogen plants have become swing producers, dependent on the domestic price of natural gas. A large proportion of nitrogen fertilizer is now imported.