Fig. 9
Regional decomposition of 50 years of production, area, and yield patterns for eight key crops in Africa: (a) maize, (b) sorghum, (c) cassava, (d) groundnuts, (e) rice, (f) cowpea, (g) sweet potatoes, and (h) sugarcane. The data span the period 1973-2022. Note that the yield values (production divided by harvested area) are smoothed with a 10-year moving mean. The yield panels also exclude northern Africa, which appears off-scale (significantly higher yield) with respect to the other regions. The central panel (i) summarizes the 5-decade-long trends in production, area, and yield. Although the total production of most crops has increased at rates of approximately 20–30% per decade, these production gains are accomplished principally through increases in harvested area (i.e., crop extensification) rather than through increases in crop yields. Typical increases in crop yields over the past 50 years are approximately 10% per decade or lower.
