WIID Companion (March 2021): gobal income distribution
This document is part of a series of technical notes describing the compilation of a new companion database that complements the UNU-WIDER World Income Inequality Database. It aims at facilitating the analysis of inequality as well as progress in achieving the global goal of reducing inequality within and across countries. This new dataset includes an annual series reporting the income distribution at the percentile level for all citizens in the world, regardless of where they live, from 1950 to the present.
The global distribution is displayed along with the country-level information used to produce it. The dataset also includes estimates of various global absolute and relative inequality measures, and the income share of key population groups. All estimates are further disaggregated by the contribution of inequalities within and between countries, as well as by each country’s geographical region and income group.
While previous technical notes described the selection of country income distribution series and the integration and standardization process to overcome the heterogeneity in original welfare concepts and other methods, I here describe all the necessary additional steps and assumptions made to construct the new global dataset.