The haves and have-nots are sticking to their own neighborhoods more than ever.

A Pew Research Center study finds that residential segregation has steadily increased in the past 30 years, the result of income inequalities that have led to a reduced share of mixed-income neighborhoods in the United States.

The report states that 28 percent of lower-income households in 2010 were in areas where the majority of the residents had similar income levels, up from 23 percent in 1980.

At the same time, upper-income households have become more clustered in neighborhoods where families are similarly upper income, the study says. In 2010, about 18 percent of  more-affluent households lived in majority upper-income census tracts, compared to 9 percent in 1980.

The study shows that predominantly middle-class neighborhoods have declined from 85 percent in 1980 to 76 percent in 2010, giving further evidence of the steady declining middle class.

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By region, the four top metropolitan areas with the most income segregation in the country include Houston, Dallas, Miami, and Los Angeles. The study cited two patterns contributing to income segregation in these regions: the immigration of low-skilled, low-wage workers from south of the border and of high-wage workers and well-off retirees.

Still, segregation by income remains less prevalent than segregation by race, according to the study.

This story is part of our Next America: Workforce project, which is supported by a grant from the Annie E. Casey Foundation.

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