There is an article in today's Post about who's coming to DC, who's staying put, and who's leaving town. Essentially the piece is mostly stuff that you've seen before (new numbers, but you already had the idea):
1. DC's population shark between 2000-2004 *The city doesn't like to admit this is true since they are supposedly trying to attract new residents to raise the District's population. But who are they kidding? You take a house with a big family living in it (maybe the adult children still live with their parents?). You sell this house to some young couple for half a million dollars, and the original inhabitants hightail it to Prince George's. Now repeat the process, but this time do it with a big rooming house, or a place that used to be split into apartments. How do you not lose population?
2. DC is attracting more people age 25-34.
3. DC is losing people age 35-54 *News flash! Residents leave the city when it's time to have kids!
So once again it comes down to the school system. DC can't retain families because as, a whole (obviously there are exceptions), the public schools suck.