The World Top Incomes Database has been cataloguing statistics on wealth across the globe since 2011, and its creators have used that data to inform several books, including economist Thomas Piketty's study of income inequality, Capital in the 21st Century, which was published in English just a couple months ago. Piketty and the creators have left the database's information open to the public too, and now two members of Carnegie Mellon University's Robotics Institute have turned that data into an interactive map that allows you to explore income inequality across in globe, in part as a way to complement Piketty's book.
Inequality dipped in the mid 1900sThough the interactive is a simple enhancement of Google Maps, it lets viewers get a good impression of how income inequality has changed in certain areas across the globe. The map includes around a century of data on 29 countries, primarily those in Europe and East Asia, as well as the United States and Canada. A significant number of those countries, including the US, follow a similar trend of having high inequality on either end of the 1900s, but significantly narrower income inequality between the mid-1940s and the mid-1980s.
There are a number of ways to explore the map, as well as an accompanying chart, all of which involve viewing it based on how much income is heading to the wealthiest in a given country. Two maps allow viewers to see what percent of all income is flowing to the wealthiest in each country, either the top 1 percent or the top 10 percent, and another two others allow viewers to see how much more people in the top 10 percent bracket are earning than those in the bottom 1 percent or bottom 10 percent. The database's information was all gathered from income tax records, and researchers Randy Sargent and Christopher Bartley put together this new interactive.