The graphic above is arresting. This comes from the [Economic Policy Institute's upcoming State of Working America report](http://www.epi.org/economic_snapshots/entry/state_of_working_america_pre...), and it gives the lie (again) to any notion of equal opportunity in America. It's a bit complex at first glance, but actually makes a quite simple point: Upward mobility is a myth for a huge percentage of black Americans, including those who were born into the middle class. Economists often measure mobility by dividing the population into five income tiers. Each column of this chart reflects the percentage of kids born into that income tier who, as adults, fell to the bottom income tier. So in 2008, 45 percent of African Americans who were born into the middle class, measured by income, were living at the bottom income level as adults. That was true for only 16 percent of whites born into the middle class. Meanwhile, over half of black people who were born into poverty remained there as adults, while about two-thirds of whites had moved up the income ladder. The point is plain: economic mobility is not the same for everybody in America, and to the degree we can talk about a genuine black middle class, it's not a terribly secure one.