Washington has had a significant African American population since the city's foundation. African American residents composed about 30% of the district's total population between 1800 and 1940. The black population reached a peak of 70% by 1970, but has since steadily declined due to many African Americans moving to the surrounding suburbs. Partly as a result of gentrification, there was a 31.4% increase in the non-Hispanic white population and an 11.5% decrease in the black population between 2000 and 2010. According to a study by the National Community Reinvestment Coalition, D.C. has experienced more "intense" gentrification than any other American city, with 40% of neighborhoods gentrified.