The World Bank - GINI
The World Bank publishes the Gini Coefficient on a yearly basis. This Index (0 to 100) shows the equality (low levels) and the inequality (high levels) of distribution of wealth within a country. Raw data are household surveys in the countries or data from the World Bank country offices. Data for countries with a high income are taken from the Luxemburg Income Study database. As there is no constant global annual data set for the Gini coefficient, the values indicated mirror the data of the past 10 years. Data used to calculate the Gini coefficient were/are only collected and calculated for a share of all countries on a yearly basis.