Comparing global inequality of income and wealth

This paper is the first to compare global trends in income and wealth inequality this century. It is based on large income and wealth microdata samples designed to be representative of all countries in the world. Measured by the Gini coefficient, inequality between countries accounts for about two-thirds of global income inequality, but noticeably less - around one half - of wealth inequality. Broadly similar results are found for different years and different inequality indices, bar the share of the top 1 per cent. Over time, changes in countries' mean income and wealth, and population sizes, have reduced world inequality. Income inequality has changed little within countries, so the downward trend remains intact. However, within-country wealth inequality has risen, halting the downward shift in global wealth inequality and raising the share of the top 1 per cent after 2007.