FAO data show that Rwanda lost much of its yield superiority to similar countries in the region during the 1980s falling behind in cassava, maize, and sweet potato, and, in comparison to some neighbors, in coffee. Rwanda still has, however, comparatively high yields in its main cash crops white potatoes, sorghum, coffee, and tea. Farm size affects yields. Smaller farms produce much more on each additional hectare of land than what is paid for a hectare of rented land. But smaller farms produce much less for each additional day of farm work than it costs to hire a worker for a day.
Erosion greatly reduces yields.
The gain is as high as 33 percent for farms with a high share of subsistence annual crops and high erosion. The yield gains from shifting to cash cropping are highest for those with low levels of soil erosion and high use of fertilizer and organic matter. Growth of agricultural output must keep pace with rapid population growth, and is necessary to build trade ties in the region and abroad. This will require greater use of improved inputs. Without political stability it will not be possible to expect productivity investments.