Thirty-two percent of black people born in DC still live there, but only 4% of white people born there do. Where they've moved to also differs greatly by race. This disparity arose from racial and racist policies in our history.Last year, The New York Times created a set of fascinating charts that illustrate migration patterns between US states. The out-migration chart for the District showed that almost half of the people born in the city had moved to Maryland or Virginia.The experiences behind these figures differ greatly for black and white Washingtonians. These two graphics attempt to break down the original chart to tell these two distinct stories, using data from the US Census Bureau retrieved through the University of Minnesota's Integrated Public Use Microdata Series . All numbers and percentages discussed only represent movement between the District and other US states; they don't represent migration out of the country.White Washingtonians first began moving to Maryland in droves in the 1940s (that's the first big bump in the second chart), but blacks were excluded from this migration pattern for another three decades. Private housing developers and neighborhood associations used restrictive covenants to ensure that only whites would live in these communities (this practice was occurring within DC as well, and everywhere else , and had been commonplace for decades). Most public housing developments, such as those in Greenbelt, Maryland , developed in 1937 for whites-only, were segregated too.In 1948, the Supreme Court ruled that the government could not legally enforce these covenants. Private parties, though, could continue to honor the terms, and they did.In addition to being excluded from white neighborhoods, which included almost all communities adjacent to but outside of the District, black Americans faced other forms of harsh housing discrimination. Federal intervention in the mortgage industry revolutionized the housing finance system in the US starting in the 1930s and 40s by supporting cheap, long-term mortgages with low down payment requirements. But only whites were able to take advantage of these products.In the National Capital area, two-thirds of these loans were made to homebuyers outside of the District's boundaries and almost all loans, everywhere , were made in predominately-white areas. Add to the mix the practice of racial steering and the reality of gaping income disparities between blacks and whites, and it is no surprise that before the 1970s, less than 10% of all District-born blacks lived in Maryland and Virginia (including all the cities in those states, not just the communities close to DC). The Fair Housing Act of 1968 did not eliminate race-based housing discrimination, but did make it illegal, vastly increasing minority access to areas from which they had been previously excluded. In 1970, 8% of District-born blacks lived in Maryland. By 1980, that share more than tripled to 27%.Black migration from DC to Maryland continued to increase from 1980 to 2000, but at a slightly slower pace. It has since plateaued, with approximately 44% of District-born blacks now residing in Maryland.Most of the moves the District-born black population has made over the last four decades have been to Prince George's County. More District-born blacks live in Prince George's County than live in the entire District of Columbia, with 33% living in the county. However, that percentage seems to have leveled off and remained steady since 2000.More and more DC-born blacks are heading to new destinations, both in nearby places like Charles County (70% increase between 2000-2010) and more distant ones like North Carolina (46% increase between 2000-2010). There are more District-born blacks in North Carolina than there are in the entire Northeast region of the country, and more than in the entire West and Midwest regions combined. Many are moving to other parts of the South too, with notable clusters emerging in and around Atlanta and Memphis.Very few white people who are born in the District stay there, although that trend appears to be reversing slightly after reaching a low point in 2000, when the percentage was less than 3%. The history behind these figures has been partially described in the paragraphs above: whites enjoyed all of the opportunities blacks were denied.Huge numbers of white Washingtonians left the city between 1940 and 1960. About 42% of those who left moved to Maryland, and 17% moved to Virginia. Small but growing numbers moved west and south, particularly to California and Florida. These trends continued, but after 1990 Maryland started to see its share of District-born whites decline as people continued to move increasingly West and South (a trend not unique to those born in DC).The clear differences between how black and white residents born in the District have moved around the United States highlight important elements of our history. The steady flow of white Washingtonians out of the city, which accelerated starting in the 1940s, reflects a population taking advantage of public policies designed to help them build wealth.Meanwhile, black Washingtonians' lack of mobility illustrates how policy makers discriminated against blacks for at least another three decades while their white counterparts solidified their middle-class, home-owning status. These charts tell the story of blatant institutional racism targeting blacks 40 years ago, not 400.Access to education, employment, wealth, and safety are closely tied to geography. It's imperative that our current and future public policies foster access to these opportunities for black Washingtonians and other traditionally excluded groups so that the next version of these charts conveys progress rather than continued inequality.