Our take: More higher-income households are living in neighborhoods that are wealthier, and on the other side, more lower-income households are living in poorer neighborhoods in America.

So, the question is, because there are fewer people in the middle, has it affected where we live and with whom we live and what our neighborhoods look like? And the answer from this report is yes.

There's actually more movement up than down, at least when you do the breaks the way we did. But, increasingly, there's also not just a smaller middle, but there is an increasing tendency of people at the upper end to live among themselves and people at the lower end to live among themselves.