(CNN) It's pretty well established that racial segregation limits access to jobs, education, public services and other resources for people in high-poverty neighborhoods.

But how does economic and racial segregation in a handful of neighborhoods affect the rest of a metropolitan area?

The Urban Institute, in collaboration with the Metropolitan Planning Council, analyzed data from the 100 most populous metro areas in the 1990, 2000 and 2010 censuses and found that less segregated regions had higher average incomes and educational attainment and lower homicide rates.

And despite efforts to integrate schools and neighborhoods, the report concludes that the United States remains "starkly segregated" by race and income. That leads to worse regional outcomes on the whole, the report says, though trends vary across the country.

The report argues that more inclusion builds safer, smarter and richer regions.

Economic and racial segregation tend to go hand in hand

Regions with more segregation between blacks and whites are more economically segregated, the study found. The relationship is weaker when measuring Latino-white segregation.

The metro areas with the highest composite economic and racial segregation rankings in 2010 were:

- Philadelphia

- Bridgeport, Connecticut

- New York

- Milwaukee, Wisconsin

- Chicago

- Cleveland

- Newark, New Jersey

- Los Angeles

- Kansas City, Missouri

- Detroit

To define a metropolitan area the report uses the census definition of a commuting zone, which is a group of counties whose commuters form a unified regional labor market.

Six of the top 10 were the same in 1990 and 2010. Bridgeport, Los Angeles, Kansas City and Detroit replaced Gary, Indiana, and Houston, Washington and Dallas.

Economic segregation is on the rise

In regions where there is a high level of economic segregation, access to education, jobs, housing and public services is largely concentrated in the areas where high-income people live, and far away from where low-income people live.

This kind of economic segregation can take a toll on the economy of the region as a whole, because it keeps workers away from potential employers.

Places with greater segregation between low- and high-income people also tend to have greater income inequality on the whole.

What does an economically segregated region look like? Take for example New York City, which tops the list. People living in affluent neighborhoods reap the benefits of good schools, low crime rates and access to public services, while those priced out of those areas may have to travel farther for access to services, work or school -- if they can afford the trip at all. The result is uneven distribution of wealth, which keeps poor neighborhoods poor and limits potential spillover effects of affluence.

Previous studies have found that economic segregation is higher today than it was in 1970, with the share of Americans living in middle-income neighborhoods dropping from 65% then to 42% in 2009.

The report takes a closer look at the trend. It found that between 1990 and 2000, economic segregation decreased in 92 metropolitan areas. Then, in 2000, the trend began to reverse and from 2000 to 2010, economic segregation increased in 72 areas as high-poverty and high-affluence neighborhoods began to outnumber mixed-class, middle-income neighborhoods.

Racial segregation is slowly declining...

...sort of. Black-white segregation in the 100 metro areas examined in the report dropped on average, from 1990 to 2010, while Latino-white segregation increased.

In general, however, blacks and whites tend to be more segregated from one another than Latinos and whites.

Whites tend to benefit most from high degrees of racial segregation, according to the study. They earn higher wages, complete college at higher rates and get higher-status jobs. Segregation undermines these same outcomes for Latinos and blacks, thereby limiting the segregated region's potential to boost its overall economic prospects.

Segregation is most detrimental for black people

When people have access to safer neighborhoods and better schools, their educational attainment and job prospects improve, benefiting the entire population of a region, the study's authors argue. Steady, high-paying jobs increase individual and per capita incomes, which means cash flows back into communities through home ownership, taxes and consumer spending.

When levels of segregation are high in a region, black residents tend to suffer most, the report found.

Higher levels of economic segregation are associated with lower median and per capita income for blacks. Additionally, higher levels of racial segregation are associated with lower incomes and lower educational attainment for blacks.

The effects add up. Higher levels of black-white segregation are associated with lower levels of educational attainment for blacks and whites and lower levels of safety for all area residents.

On the other hand, neither economic segregation nor racial segregation is significantly related to white or Latino median or per capita income.

Using Chicago as a case study, the report's authors argue reducing racial and economic segregation to the median level could increase black per capita income and educational attainment and lower the homicide rate.

"If actors at the city, county and state levels could break down barriers to local inclusion, entire regions could benefit from higher incomes and education levels and fewer homicides," the authors write.