“East of the river” has long been part of the District’s vernacular, referring to the physical and socioeconomic divide formed by the Anacostia. But an analysis released Wednesday puts demographic differences between the city’s two sides in sharp relief, painting a bleak picture of social equity in D.C.

The D.C. Fiscal Policy Institute (DCFPI) dug deep into the latest data from the U.S. Census Bureau, released a couple of weeks ago, and compared the area east of the Anacostia River to the rest of the city. (Helpfully, the bureau just so happens to divide D.C. into five statistical zones, one of which corresponds to the land east of the river.)

Although the District’s two sides have historically shown disparities, DCFPI found that the growth seen in the city as a whole during the post-recession era has not crossed into Wards 7 and 8, and that fewer black residents live on the city’s west side. Overall, east of the river neighborhoods displayed a poverty rate that is three times higher than the rest of D.C.

“What was really striking was the extent to which D.C.’s African American residents and poor residents increasingly live east of the river,” says Claire Zippel, an analyst for DCFPI. “We have a greater share of our black residents living in an area of the city that has serious economic challenges, which has implications for people’s ability to succeed in the future.”

According to the advocacy organization, 21,000 fewer black residents live west of the Anacostia River than before the recession, resulting in a decline from 42 percent of west-of-the-river population in 2007 to 33 percent last year. Meanwhile, more than 90 percent of residents living east of the Anacostia are black, composing almost half of the District’s total black population (47 percent).

Additionally, the poverty rate east of the river increased from 27 percent before the recession to 33 percent in 2015. It ticked down a percentage point west of the river, to 12 percent, over the same period. The proportion of the city’s residents who live below the federal poverty line jumped from 40 percent in 2007 to 47 percent last year.

“Median income for the city as a whole rose to $75,600 in 2015, from $62,100 in 2007, adjusted for inflation,” DCFPI says. “Yet median income for households living east of the Anacostia River remained stuck at just $34,000.”

While the data doesn’t reveal the specific reasons individuals may have moved from the District’s west side to its east side (the increasing cost of housing, say), DCFPI argues that lawmakers should focus on policies that blunt the forces of displacement that low-income and African American residents face. Among them: strong community benefits in east-of-the river developments like job training and local hiring, and preserving affordable housing in west-of-the-river neighborhoods where owners have incentives to up rents or convert units into condos. 

You can read the full analysis here.