The UNU-WIDER World Income Inequality Database (WIID) collects and stores data on income inequality for developed, developing and transition countries.
The updated WIID, Version 3A (now available for download), gives researchers access to data on eight new countries and over 2,000 additional observations, as well as numerous corrections to the previous dataset.
Since its first publication in 2000, the WIID has become a vital resource for those interested in the study of inequality, and has made significantly easier the task of comparing income inequality over time and space.
The period covered by the database has been extended in this new version by seven years, with the latest observations now coming from 2012. Quality ratings of the data provide researchers with the ability to decide for themselves which measurements to include in their analysis.
WIID Version 3A consists of a checked and corrected WIID Version 2 as well as new estimates from National Survey statistics obtained from the respective country official websites, the Socio-Economic Database for Latin America and the Caribbean, Transmonee, Luxembourg Income Study database, OECD and Eurostat.
The updated WIID will continue to contribute to better-informed studies of inequality, and increase debate about its causes and consequences.