Nationwide, 55 percent of the poor population in metropolitan areas is now in the suburbs, up from 49 percent.http://www.nytimes.com/2011/10/25/us/suburban-poverty-surge-challenges-communities.html?_r=1&hp&gwh=86CD8107F743F2DB40D740F94DA10A95
One of the worst experiments in human history with the advent of cheap oil. it's very environmental not friendly. all things are spread out, no density and economics of scale for all things.
Wealth flew into the suburbs after ww2 and now with some parts of the cities gentrifying. hopefully this will mean a end to it.