This indicator is part of the FAO Suite of Food Security Indicators (2017) in the dimension "stability".
Per capita food supply variability corresponds to the variability of the "food supply in kcal/caput/day" as disseminated in FAOSTAT.
The per capita food supply variability compares the variations of the food supply across countries and time.
Missing values in the dietary energy supply are interpolated using a linear trend. The series is then detrended by fitting a cubic spline by ordinary least squares to the series. The difference between the cubic fit and the acual values are then calculated. Lastly, the volatility for a specific year is defined as the standard deviation of these differences over the previous five years. The aggregates are computed applying the same methodology to the aggregates of the food supply variable.
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