Global cereal yields have increased a lot, but millet and sorghum lag behind

Global average yields of cereal crops have tripled over the past 60 years. This has been crucial to feeding a growing population while sparing natural habitat from expanding agricultural land.
However, some cereal crops have seen much larger gains in efficiency. Maize (corn) and rice achieve the highest yields and have seen huge gains in recent decades. Wheat and barley have also performed well.
As this chart shows, crops like sorghum and millet have lagged behind. A hectare of land could yield 5 to 6 tonnes of corn or rice but only 1 to 1.5 tonnes of millet and sorghum.
It’s not just that yields for these crops are much lower today; growth over the past 60 years has been much more modest, increasing by less than 50%. This is a huge challenge since these are key staple crops across much of Sub-Saharan Africa, where hunger rates are the highest and farmer incomes are the lowest.