Comparing the Racial Segregation of U.S. Cities

The City Observatory used American Community Survey from the U.S. Census to compare the segregation of the largest U.S. cities. Portland is the most integrated American city; Detroit is the most segregated U.S. city.

2 minute read

August 23, 2020, 11:00 AM PDT

By James Brasuell @CasualBrasuell


Portland Weird

Josh Rainey Photography / Shutterstock

Joe Cortright shares an investigation into the racial segregation of the largest cities in the United States, using a Dissimilarity Index, "which measures the extent to which different groups of people live in different neighborhoods in a city or metro area," built on American Community Survey (ACS) and the previous work of the St. Louis Federal Reserve Bank.

"The index ranges from zero (perfectly integrated, where the composition of each neighborhood matches the composition of the larger region) to one (completely segregated) where each neighborhood consists entirely of persons of a single racial or ethnic group)," explains Cortright of the way the Dissimilarity Index measures segregation.

The tabulation shared by Cortright includes only central counties with populations of 100,000 or more, producing quite a bit of variation, once cities start to deviate from the median. "The median large metro area has a dissimilarity index of 45, meaning that about 45 percent of a city’s population would have to move to balance the composition of individual neighborhoods to the region’s overall demographic composition. About half of all large cities have dissimilarity indices between about 38 and 54," according to Cortright.

When it comes to ranking cities in terms of their relative segregation or integration compared to other U.S. cities, the cities with the highest levels of segregation are Detroit, New Orleans, Philadelphia, Buffalo and Milwaukee, according to Cortright, each with a dissimilarity index exceeding 60.

On the other end of the spectrum, the cities with the lowest levels of segregation are Portland, Virginia Beach, Boston, Seattle and Las Vegas, according to Cortright.

Cortright also notes that the ACS data also allows for segregation to be measured over time. "For most large US metro areas the trend in segregation is downward: Dissimilarity indices are declining over time," according to Cortright.

The article also includes more details about the historic downward trend of segregation in Portland.

Tuesday, August 18, 2020 in City Observatory

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