This indicator is calculated by FAOSTAT/ESS and is part of the FAO Suite of Food Security Indicators -- Dimension: access (http://www.fao.org/economic/ess/ess-fs/ess-fadata/en/#.WTlX9BPytPU). It estimates the number of people at risk of undernourishment and it is calculated by applying the estimated prevalence of undernourishment to total population in each period. The indicator is calculated in three year averages, from 1990-92 to 2014-16, to reduce the impact of possible errors in estimated DES, due to the difficulties in properly accounting of stock variations in major food. (Source: Faostat - http://www.fao.org/faostat/en/#data/FS).
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