At the risk of sounding racist, but there is a lot of white flight from DuPage, lake and kane counties. The white population left chicago in the 50s-70s to the burbs. Those former white neighborhoods became black.
Now the black population is getting pushed out by the Hispanic population. Blacks are pushing out into the burbs. Whites are leaving DuPage, kane, and lake. They are ether moving out of state or moving to the outlining counties where the taxes are lower and there is no music shaking your windows at 3am.
I grew up in the fox valley area. Everytime I go back for a visit it seems less America.