In the twentieth century after the Great Migration from the South and concentration of blacks on the South Side due to "de facto" residential segregation, the district became the nation's first with a black-majority population. Since the 1920s, it has included the central area of Chicago's South Side African-American community. Over 85% of the district's residents were black during the period from the 1950s through the 1980s, but redistricting since that time – which redrew the district lines with the goal of maintaining three Chicago districts with black populations exceeding 60% – has reduced the percentage of black residents in the district to 70% in the 1990s. The current figure is 65%. Outward migration has caused the South Side's population to decrease over the years, and the district was expanded geographically to the southwest to gain residents, particularly as the state's congressional delegation has been reduced in numbers due to population changes and reapportionment. The district, which covered only nine square miles in the 1950s, is now more than ten times that size. Nearly half its current area was added for the 2000s.