Here is a nifty little tool from the NYT that shows income mobility by county: The Best and Worst Places to Grow Up. It will automatically center on the county it thinks you are browsing from.
My hometown of Spalding, GA is not a good place to be born poor. If you are born poor in Spalding, there is a very, VERY high chance of remaining poor for the rest of your life.
It ranks 17th out of 2,478 counties, better than almost no county in the nation.
Ever year you live there as a child takes $220 from annual earnings. So a person who lived in Spalding from birth until 20 years old will make $4,500 less per year by the age of 26, compared to the national average.
Even the average-income and rich kids take an income hit by growing up there. Only the top 1% of Spaldingites are able to eek past the National average.
If you move one county over, to Pike or Fayette, as many of my family members have, things start to look a little better. Living in Pike takes only $10 per year of childhood there, not a bad price for living in the beautiful countryside. Poor boys were still able to beat the national average of income at 26 by a hair ($190) while girls are still doing a little worse (-$680). Interestingly, girls in the top 1% fair better than their male counterparts.
If you move one county over in the other direction to Fayette, the situation drastically improves for poor kids while the 1 percenters seem to be about breaking even with their national peers.
The data comes from the NYT and the Equality of Opportunity Project by Raj Chetty and Nathaniel Hendren at Harvard.