The N fertilizer costs and consumption of specific countries for past use and future forecasts.

Italicized text represents future estimates and are based on no increase in consumption (EU and Denmark) or a linear increase in consumption, equivalent to the rate of increase between 1987 and 2007 (world and China) (http://www.fao.org/corp/statistics/; accessed 16 June 2010).aEstimates of World N consumption in 2020 are 110 MMt [55], 112 MMt [56], and 135 MMt [57].bEstimates of World N consumption in 2030 are 125 MMt [56].cEstimates of World N consumption in 2050 are 135 MMt [58] and 236 MMt [57].MMt, million metric tons.