Note: This is our 2025 update to the our report published in 2021. Click here to view the original.
--The Othering and Belonging Institute is pleased to unveil a major update and extensive addition to our “Roots of Structural Racism” project examining national patterns and dynamics of racial residential segregation in the United States. This project launched in 2021, and included a comprehensive presentation of our main findings, an interactive mapping tool that allows users to observe these dynamics using a wide range of measures, a repository of local histories of segregation, and much more.
This update includes the following major components:
1. New & More Recent Data
We added a new year to our map: 2023, based upon the American Community Survey results, a census survey that includes more recent data than our 2020 census update. This page will give us new insights into the continuing evolution of segregation in America.
2. New Measures of Segregation
- We have added four new economic segregation measures - income entropy (a diversity measure), neighborhood categorization, income polarization and Dissimilarity Index for income segregation.
- We also added new racial segregation measures. Most importantly, we added a measure known as “Thiel’s H,” or the Multigroup Entropy Index, which some scholars regarded as the best measure of racial residential segregation.
- Although not a new update, in 2023, we quietly added the Diversity Index to our mapping tool as well.
We have updated our Technical Appendix to include descriptions of the four new measures of economic segregation and Thiel’s H. This includes a previously added description for the Diversity Index.
3. Mapping Updates
We have updated our interactive mapping tool to feature many new important elements.
- Updated Boundaries: The entire map has been updated to the 2020 census boundaries. Our previous map was coded to 2010 boundaries. A more detailed and direct data available for 2020 Census boundaries helps us accurately share the impact of segregation on CBSAs, counties and cities in the US.
- New geographies: We have added all counties to the map so that you can now generate measures and data for every county in America. Previously, you could only look at counties that fell outside of metropolitan areas.
4. Improved / Sortable Tables
Critically, unlike our previous “most segregated cities” and “metro areas” pages, the new pages are presented in a sortable table where you can select the measure of segregation you prefer. We have made the Divergence Index the default, but you can now re-rank them according to your preferred measure.
We have also updated our 2020 census “most segregated/integrated” cities and metropolitan areas pages to also include a sortable table. The original list is featured below that sortable table.
5. New Insight and Analysis
We feature a new essay that compares all of the major measures of racial residential segregation over time, to present and analyze how they behave over the time of our study. This new essay provides original insights into the behavior and dynamics of these measures.
6. Corrections
We have corrected minor or relatively technical errors in our main report, including an incorrectly presented graphic on political polarization. A full list of corrections is presented below.
Project Corrections
- Corrected error in missing metros: The previous version accidentally removed five metro areas from the analysis due to coding error. The error has been fixed in this version.
- Updated political polarization chart: The previous version showed the scatter plot between percentile ranking of Divergence and Metropolitan Political Segregation. The chart has been updated with the Divergence score and Metropolitan Political Segregation along with the updated correlation coefficient.
Main Findings
- As before, we find that 55% of metropolitan areas (CBSAs) are more segregated in 2020 than in 1990, based on the Divergence Index. Inversely, 45% of CBSAs are less segregated in 2020 than in 1990 based on the Divergence Index.
- Part of this may be related to increases in diversity. We find that 98% of CBSAs had a higher entropy score in 2020 than in 1990.
- The top 10 most segregated cities (at or above 200k population) in the country, as of 2020, are Detroit, Newark, Hialeah, Chicago, Milwaukee, Cleveland, Birmingham, New York City, Irving, and St. Louis. Miami is no longer in the top 10 list.
- The top 10 most segregated cities (at or above 200k population) in the country, as of 2023, are Detroit, Newark, Hialeah, Milwaukee, Chicago, Cleveland, Irving, Birmingham, New York City, and Philadelphia.
- The top 10 most segregated metropolitan areas (at or above 200k population) in the country, as of 2020, are Chicago, New York City, Miami, Milwaukee, Detroit, Trenton, Cleveland, Los Angeles, Port Arthur and Atlanta. The list of metros are the same as reported in the last update in October 2021, but the order is different.
- The top 10 most segregated metros (at or above 200k population) in the country, as of 2023, are Chicago, New York City, Miami, Detroit, Memphis, Trenton, Port Arthur, Cleveland, McAllen and Monroe.
- The most integrated or least segregated cities in 2023 are Port St. Lucie, FL; Colorado Springs, CO; and Fayetteville, NC, and none of the metro areas qualify to be the most integrated or least segregated in 2023.
