Dylan Matthews explains the above chart on global inequality:

[C]lass rank matters far less than location in determining where someone falls in the global income distribution. That’s a big change from the 19th century, where class rank predominated. [Branko Milanovic, the lead economist at the World Bank’s research group] argues this means we live in a “non-Marxian world,” where the relevant cleavage is not between the proletariat and the owners of capital but between those with the misfortune to be born in poor countries and those with the great fortune not to be. “A proper analysis of global inequality today requires an empirical and mental shift from concerns with class to concerns with location,” he writes. “In other words, a movement ‘from proletarians to migrants.’”