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Vincent Ricciardi, Navin Ramankutty, Zia Mehrabi, Larissa Jarvis, Brenton Chookolingo, How much of the world's food do smallholders produce?, Global Food Security, Volume 17, 2018, Pages 64-72, ISSN 2211-9124, https://doi.org/10.1016/j.gfs.2018.05.002.

The widely reported claim that smallholders produce 70–80% of the world’s food has been a linchpin of agricultural development policy despite limited empirical evidence. Recent empirical attempts to reinvestigate this number have lacked raw data on how much food smallholders produce, and have relied on model assumptions with unknown biases and with limited spatial and commodity coverage. We examine variations in crop production by farm size using a newly-compiled global sample of subnational level microdata and agricultural censuses covering more countries (n=55) and crop types (n=154) than assessed to date. We estimate that farms under 2ha globally produce 28–31% of total crop production and 30–34% of food supply on 24% of gross agricultural area. Farms under 2ha devote a greater proportion of their production to food, and account for greater crop diversity, while farms over 1000ha have the greatest proportion of post-harvest loss.