Occurred throughout the twentieth century, due to diverse causes current trends include middle-class african-american families following white flight patterns out of cities, while affluent whites return to cities that have historically had a black majority.

The Great Migration

Explanation:

It was the relocation of millions of African Americans from the rural south to the cities of the North, Midwest, and West. It started in 1916 till 1970. The reasons for migrations were unsatisfactory economic opportunities, Segregationist laws. Those who migrated towards the north became industrial workers. During the migration, they build a new place for themselves in economic life and also started to confront Racial prejudice.

i know social security wasn't one.

explanation:

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