US2020

RESIDENTIAL SEGREGATION

The following pages contain non-Hispanic white, non-Hispanic black, Hispanic, Asian and Native American population data. You can use the data to learn about the racial/ethnic composition of a city or metropolitan region. Use the dissimilarity index to determine differences in residential patterns of one ethnic/racial group in relation to another. The racial/ethnic composition of the neighborhood where the average member of a particular group lives is determined by using the exposure index, and the percentage of same-group population in the census tract where the average member of a racial/ethnic group lives is shown in the isolation index.

You can choose to view data for a city or for a metropolitan statistical area (MSA).

City Data
We have calculated data for all cities with more than 10,000 population in 2010. Note that some indices become unreliable or have little meaning for very small places, or where a specific racial/ethnic group is very small. Therefore, you should be cautious in using these data, especially for cities with populations less than 50,000.

Metropolitan Region Data
The Census Bureau uses a standard set of definitions of the area included in each "metropolitan statistical area" (MSA) or "metropolitan division.” In most cases they include both a principal city (or sometimes two or more principal cities) and the ring of surrounding suburbs. At the top of the page for each metro area, we have listed the counties and the city or cities that the census has designated as principal cities for this area. After viewing data for the entire metropolitan area, you may select to see information for only the city or suburban portion. If there is more than one principal city, please remember that what we report is for all these cities combined.

A metropolitan division is a subdivision of an MSA, including a county or counties with a population core of at least 2.5 million. Metropolitan divisions are created in MSAs with very large populations (like the New York-Northern New Jersey-Long Island, NY-NJ-PA MSA), and it may be preferable in some cases to analyze the metropolitan divisions separately.

All MSAs and Metropolitan Divisions are included in alphabetical order on the “Select a Metropolitan Region” menu. The “Select a Metro Division” menu lists the 11 MSAs that have been subdivided and shows the Metropolitan Divisions within them.

Information on data to be viewed

Index of Dissimilarity
The dissimilarity index measures whether one particular group is distributed across census tracts in the metropolitan area in the same way as another group. A high value indicates that the two groups tend to live in different tracts. D ranges from 0 to 100. A value of 60 (or above) is considered very high. It means that 60% (or more) of the members of one group would need to move to a different tract in order for the two groups to be equally distributed. Values of 40 or 50 are usually considered a moderate level of segregation, and values of 30 or below are considered to be fairly low.

Exposure Indices

- Isolation Index
The isolation index is the percentage of same-group population in the census tract where the average member of a racial/ethnic group lives. It has a lower bound of zero (for a very small group that is quite dispersed) to 100 (meaning that group members are entirely isolated from other groups). It should be kept in mind that this index is affected by the size of the group -- it is almost inevitably smaller for smaller groups, and it is likely to rise over time if the group becomes larger.

- Exposure to other groups
Indices of exposure to other groups also range from 0 to 100, where a larger value means that the average group member lives in a tract with a higher percentage of persons from the other group. These indices depend on two conditions: the overall size of the other group and each group's settlement pattern.