Walmart Heirs Worth Same Amount As Bottom 30 Percent Of Americans In 2007: Analysis

The Occupy Wall Street movement has brought increased focus on the disparity between the top one percent of earners and everyone else in the United States. But one American family paints a particularly stark picture of the country's wealth gap.

The six children of Walmart's founders, Sam and James "Bud" Walton, had the same net worth in 2007 as the entire bottom 30 percent of American earners, according to an analysis from Sylvia Allegretto , a labor economist at University of California-Berkeley's Center on Wage and Employment Dynamics.

Though the 2007 figure is striking, the gap between the Walmart heirs and the rest of the country may get even bigger -- the Walton's combined fortune has grown by more than $20 billion, according to data compiled from the Forbes 400 this year .

Allegretto compared the Waltons' net worth in 2007, according to Forbes magazine , to the Federal Reserve's 2007 Survey of Consumer Finances .

The difference between the wealth of the Walmart heirs and the rest of the country epitomizes a much larger American story. The top one percent of American earners saw their incomes grow 275 percent between 1979 and 2007, according to the Congressional Budget Office, while the bottom one-fifth experienced only 20 percent income growth during the same period.

Looking at it another way: The top 10 percent of U.S. earners control two-thirds of the country's wealth and the richest 400 Americans control as much wealth as the bottom 50 percent of Americans. The difference is so stark that the public opinion has turned against it: nearly three-quarters of respondents to a poll put out by The Hill said they think income inequality is a problem.

But the rise in income inequality isn't limited to America. In 17 out of 22 countries the Organization for Economic Cooperation and Development tracks, the wealth gap has grown more pronounced since 1985 . In addition, the world's millionaires control nearly 40 percent of global wealth , according to a Credit Suisse report cited by the Wall Street Journal.

Here are fifteen things you have to know about income inequality: