The neighborhood where you live affects how successful you’re likely to be in life. If you live in a rich area, you’re more likely to get ahead; if you live in a poor place, you’re more likely to fall behind. There’s a lot of evidence to suggest places are self-reinforcing to a person’s life chances.

Despite what we hear about the gentrification of U.S. cities, many poor areas are in fact much like what they were decades ago. According to an analysis from Joe Cortright at the City Observatory, out of 1,100 urban census tracts with “high poverty” in 1970, there were 750 that still had a poverty rate double the national average in 2010. Even more disturbing, the incidence of poverty is growing. In 2010, there were three times as many areas with poverty over 30% (his definition for “high poverty”) as there were 40 years earlier.

The maps here represent these changes visually. Put together by Justin Palmer, who works at GitHub, they show changes in concentrated poverty across 51 cities. Longer arrows represent greater poverty changes, while thicker arrows show bigger populations. Red arrows indicate increase poverty; green arrows indicate less.

“I thought about ways to take these thousands of census tracts across multiple metro areas and visually condense it to a city ‘fingerprint,'” Palmer says in an email. “I loved this visualization done by the New York Times during the 2012 election that showed shifts in the electorate and wanted to see what it would look like to apply it to shifts in poverty. After a lot of trial and error, I ended up with what you see today.”

San Francisco

The City Observatory analysis, which considers tracts within 10 miles of central business districts, finds that three-quarters of poor people in concentrated poverty areas were African-American or Latino in 2010. The national poverty rate itself fluctuated between 13.7% in 1970 to 15% in 2011. This year, the poverty line is $11,770 for single people below the age of 65, or $24,250 for families of four. So people who make $12,000 a year are not technically considered poor, and aren’t even included in these maps: they should look even worse.

“It has become commonplace to observe that a person’s life chances can be statistically explained by their ZIP code,” the report says. “As a result, the composition of neighborhoods matters both for neighborhood residents as well as for public policy. Nowhere are the stakes higher, or the effects more clear, than in the nation’s high-poverty neighborhoods.”