I've heard that African Americans have been making a reverse migration in recent years. Until the 1970s, there have been more African Americans leaving the South than moving into it. Since then, more African Americans have been moving into the South than moving out. I've heard that many African Americans moving into the South say that the South today is actually more integrated. Indeed, Chicago and Detroit are some of the most segregated cities today.
That's why northern states (especially michigan) are darker on my map than in opebo's