The American Plutocracy

A new paper by Emmanuel Saez of the University of California, Berkeley, and Gabriel Zucman of the London School of Economics suggests that, in America at least, inequality in wealth is approaching record levels...
The top 0.1% (consisting of 160,000 families worth $73m on average) hold 22% of America’s wealth, just shy of the 1929 peak—and almost the same share as the bottom 90% of the population.

From The Economist, where the chart is interactive.  The phenomenon is discussed in greater detail in another article there:

Because the bottom half of all families almost always has no net wealth, the share of wealth held by the bottom 90% is an effective measure of “middle class” wealth, or that held by those from the 50th to the 90th percentile...
The 16,000 families making up the richest 0.01%, with an average net worth of $371m, now control 11.2% of total wealth—back to the 1916 share, which is the highest on record...