

It's grown 6,700% since 1983, to $144.7B in 2013 — greater than the net worth of 1,782,020 average Americans.

Everybody knows that middle-class incomes have stagnated while those of the richest Americans have skyrocketed, but trend is even more pronounced when you look at the relative fortunes of the super-duper rich. Consider the Walmart heirs: Since 1983, their net worth has increased a staggering 6,700 percent. According to a report released today by the union-backed Economic Policy Institute, here's how many Americans earning the median income it would have taken to match the Waltons' wealthin a given year.