Learn about global income inequality through an interactive visualization

United Nations Development Programme

This website is a submission to the United Nations Development Programme's
2019 Human Development Data Visualization Challenge: Visualize Inequality

Inequality is a broad multifaceted concept that is impossible to reduce to a single number or visualization; to understand it better, we must look at numerous perspectives (income, wealth, education, health, access to technology, and a multitude more). This data visualization is just a single exploration: a snapshot in time comparing the distributions of individual incomes of people within countries and across the world.

Income is one of the simplest ways to gauge quality of life along numerous dimensions (it correlates highly with educational, health, and other desired outcomes). Income is particularly easy to summarize (a single number per person) and is relatively straight-forward to compare across people and even nations. Looking at a distribution of incomes across a country one can usually gather a pretty accurate picture of life there.

The dataset needed for such comparisons comes from Branko Milanovic (2011).[1] The data provided included incomes measured in the country’s currency and thus required conversion to purchasing power parity (PPP) international dollars; this was accomplished with the World Bank dataset for 2011.[2] Only 3 countries from the dataset are not present in the visualization as there was a small mismatch between the two datasets. All processing steps and the code for generating the visualization are publicly available with an MIT license on GitHub.[3]

I give full credit for the choice of visualization to Branko Milanovic. I discovered this way of comparing data and have since seen it several times in his work (presentations, articles, and a book). It is an ingenious approach to presenting inequalities within and between countries. My minor addition is to indicate the absolute incomes within the charts. While exploring the data we can gain new insights. It becomes obvious that even those with the lowest incomes in some counties fare better than those with the highest incomes in many other countries. At the same time, another picture emerges: there is no “developing” vs “developed” dichotomy in the world today, but instead a broad continuum with countries steadily improving over the decades.[4]

Income inequality is a large political issue in the United States for many. Unfortunately, many of these individuals do not have a global picture in mind when thinking about inequality. While differences in income within the United States are staggering, global income inequality is worse still. My hope is that being exposed to a more-accurate global view will help people in all countries realize some commonalities (inequities that exist within each country), some differences (some countries are better at reducing these inequities), and some absolute numbers (just how much worse-off financially the lives of the world’s poorest are in comparison to the top 10%). Perhaps, with luck, some people will even start using a fraction of their income to help those who had the bad luck of being born in a worse situation.[5]