Table 1

Univariate and multivariate forecasts for years 2020 and 2050, based on trends observed in the past 35 to 40 years and their dependence on population and GDP. Parentheses showR 2 values for each regression. Levels of significance: **P < 0.0001; *P < 0.01; NS, P > 0.05. The value in 2000 is based on temporal extrapolation from the latest available data, generally 1998. Mean projections are means of the three univariate and the one multivariate projection.

Fertilizer (106MT)Irrigated land (106ha)PesticideCrop land (109ha)Pasture land (109 ha)
NPProduced (106 MT)Imported (109 1996 U.S.$)
Value in 200087.034.32803.7511.81.543.47
Mean projections
Forecast 202013547.63676.5518.51.663.67
Forecast 205023683.752910.132.21.894.01
Individual projections for 2050
Univariate
By year18662.04657.3325.81.793.90
(0.986**)(0.927**)(0.998**)(0.946*)(0.957**)(0.976**)(0.977**)
By population16656.24178.0222.21.733.79
(0.980**)(0.910**)(0.996**)(0.990*)(0.951**)(0.974**)(0.979**)
By GDP34398.376118.148.82.204.59
(0.964**)(0.904**)(0.992**)(0.995*)(0.955**)(0.973**)(0.977**)
Multivariate2491184737.0632.01.833.75
(0.989**)(0.979**)(0.998**)(0.994NS)(0.960**)(0.977**)(0.982**)