In 2011-12 the FAO methodology for estimating the prevalence of undernourishment went through a deep review, to identify the most appropriate model to describe the habitual dietary energy consumption in the population and improve the estimation of its parameters. In particular, it was introduced the skew-normal distribution.
Further refinements of the methodology were introduced in the SOFI 2014 edition. Available micro-data from surveys are now used to identify the most appropriate functional form for the habitual energy consumption. A new outlier detection method was introduced for micro-data, based on a "leave-out one cross-validation" approach. And a new estimation method was introduced to estimate variability in habitual energy consumption for countries where no survey data are available, based on the observed relation between the Coefficient of Variation, GDP per capita, the income Gini coefficient and food prices. Changes are described in detail here
Food Balance Sheets (FBS) provide essential information on the food system of a country. They look at:
i) the domestic supply of food commodities
ii) the domestic food utilization
iii) the food supply available for human consumption.
The Dietary Energy Supply (DES) derived from the Food Balance Sheets is also used for estimating the prevalence of undernourishment at national, regional and global levels.
Food Balance Sheets are prepared by FAO using official statistics provided by the countries. They are updated annually and are available for nearly all countries.
Food consumption data from National Household Surveys are analyzed to compute a set of food security statistics at national and sub-national levels (including gender disaggregated data) and to derive coefficients on the distribution of food consumption within the population (coefficients of variation and skewness). The latter are then used to estimate the prevalence of undernourishment.
Capacity development is provided on the analysis of food consumption data. The main objective is to strengthen the national capacity to produce and use food security statistics derived from National Household Surveys. Technical support is also offered for the design of proper food consumption and food security modules to be included in household surveys.
In collaboration with the World Bank, FAO has developed software – the ADePT FSM – that aims at improving the consistency and availability of food security statistics extracted from National Household Surveys (Household Budget Surveys, etc.) containing food consumption data. The derived food security statistics are crucial to assess and monitor food security at national and sub-national levels and inform food security programmes.
In line with the recommendations made at the Committee on World Food Security (CFS) Round Table on hunger measurement (September 2011), the FAO Statistics Division has compiled food security indicators aimed at capturing various aspects of food insecurity. The suite of indicators was first launched in the State of Food Insecurity in the World 2012, and it was analysed and further developed and analysed in the State of Food Insecurity in the World 2013, 2014 and 2015 reports.