Gini index

Definition

The Gini index measures the extent to which the distribution of income (or, in some cases, consumption expenditure) among individuals or households within an economy deviates from a perfectly equal distribution. A Lorenz curve plots the cumulative percentages of total income received against the cumulative number of recipients, starting with the poorest individual or household. The Gini index measures the area between the Lorenz curve and a hypothetical line of absolute equality, expressed as a percentage of the maximum area under the line. Thus a Gini index of 0 represents total equality, while an index of 100 implies total inequality.

Relevance

Income inequality can be both a driver and a consequence of the food system. As a driver, inequality can play into food production systems, the food environment, and individual factors that influence access to food. However, a food system can also contribute to income inequality through skewed distribution of the value of food across the supply chain (producers assume more risk and less of the revenue than distributors or retailers).