Segregation of African-Americans in cities and towns across the United States has dropped to its lowest level since 1910, according to a study released on Tuesday.

The Manhattan Institute, a New York-based conservative think tank, reported that "all-white neighborhoods are effectively extinct" and that black populations in urban ghettos are in decline based on analysis of census data from neighborhoods.

Immigration and gentrification helped convert ghettos into racially-mixed communities and contributed to diversifying suburbia, according to economists Edward Glaeser of Harvard University and Jacob Vigdor of Duke University, who co-wrote the study.

The Hispanic population has increased nationwide since the 1990s, with Latin American immigrants settling in both predominantly black and white neighborhoods, the report said. The typical African-American now lives in a neighborhood that is 14 percent Latino.

Some experts, however, argued that the decline in desegregation in residential areas has not meant an end to racial inequality. Minorities at every income level tend to reside in poorer neighborhoods than whites with comparable incomes.