clipped from: www.youtube.com   
clipped from: lcurve.org   
The red line represents a graph of family income across the population. The height of the curve at any point is the height of a stack of $100 bills equalling that income.
The L-Curve graph represents income, not wealth. The distribution of wealth is even more skewed.  Quoting from a recently-published book by political philosopher David Schweickart,
If we divided the income of the US into thirds, we find that the top ten percent of the population gets a third, the next thirty percent gets another third, and the bottom sixty percent get the last third. If we divide the wealth of the US into thirds, we find that the top one percent own a third, the next nine percent own another third, and the bottom ninety percent claim the rest. (Actually, these percentages, true a decade ago, are now out of date. The top one percent are now estimated to own between forty and fifty percent of the nation's wealth, more than the combined wealth of the bottom 95%.)