Economists Emannuel Saez and Gabriel Zucman (both known for past collaborations with Thomas Piketty) have a new paper out that takes a new approach to computing wealth information from income tax data, which lets them get a detailed look at the wealth of the very wealthy. There's a lot going on in the new working paper, but the basic empirical finding is here:

The basic punchline is that wealth — accumulated asset ownership — is very, very concentrated and has been growing more concentrated for a generation. Back in 1980, 0.01 percent of the population owned three percent of national wealth. Today that top 0.01 percent, about 32,000 people, owns about 11 percent of national wealth. That's a staggering increase from an already high base.

To learn more, watch Ezra Klein explain how wealth inequality can undermine American democracy: