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Looks like things are going pretty well! (ICIC)

It’s easy to look at topline poverty statistics—-like in D.C., where the percentage of people living under the federal poverty threshold has declined over the last decade. From that number, you might conclude that citizens of a city are doing better economically, like Initiative for a Competitive Inner City founder Michael Porter did in a presentation last month at the organization’s annual summit (see diagram from his powerpoint above). Economic revitalization in Washington must be a success, right, if its residents are wealthier than they were ten years ago.

In the District, of course, anecdotal evidence suggests that something else is going on: Higher-income people have decided that the city’s worth moving to and staying in. Under pressure from higher housing values, lower-income people are leaving for more land in places like Prince Georges County, while higher-income people decide that the city’s a good place to live. But I’ve had a hard time proving that, statistically. Plotting income levels against population increases across the city’s 188 census tracts yields no real correlation. Migration is a tricky thing to track.

The experts, apparently, don’t really know either. The Examiner‘s analyst thinks that the decrease in number of people receiving food stamps is evidence that poor people are leaving, not getting less poor. I also asked Peter Tatian, of the Urban Institute, who suggested that the decrease in the percentage of people without high school degrees, from 22 percent in 2000 to 15 percent in 2005-2009, is a result of more educated people moving in, not the D.C. school system graduating more kids.

Regardless, before celebrating decreases in the inner-city poverty rate, it’s important to consider whether existing residents are doing better, or whether new residents are just bringing up the average.