Am I one of the few that believes the most recent 2006 Census Bureau estimates for some of these cities, namely Detroit and DC, are "cooking the books" and not reflecting the actual declines ? Some of the numbers just don't pass the smell test. I don't buy the "levelling off" or even small growth (!) claims that the numbers give rise to. Even the estimates for NOLA (which showed the substantial drop from post-Katrina) seemed awfully high (perhaps by 25% or more).
Ironically, in my own city of Nashville, the CB has been substantially undercounting our population growth (currently by between 30-40k, which is around 7-8% undercount). They were pulling that stunt in the '90s when they were claiming "only" 10k-15k growth was estimated by 2000, when it turned out that we had our highest influx of residents in decades and was between 4 and 5 TIMES that number. There definitely seems to be some shenanigans going on at the CB with padding figures for non-White urban areas. Either it's stupidity or it's a political agenda, and I think we can guess which.
Detroit, maybe, but there's a been a ton of gentrification and building activity in D.C. so I wouldn't be surprised if the population leveled off.
I think the Census estimates are based in part of income tax returns which makes you wonder how many people don't show up in that system, either as having lived there or having left.