Wayne State University researchers Jason C. Booza, Jackie Cutsinger and George Galster are the authors of a recently released study for the Brookings Institution suggesting that there has been a sharply increasing neighborhood economic polarization during the last three decades. Titled \"Where Did They Go? The Decline of Middle-Income Neighborhoods in Metropolitan America,\" the Brookings study analyzed census family and neighborhood income data from 1970 to 2000 for the country\'s 100 largest metropolitan areas and the cities and suburbs of a dozen selected regions, including the Baltimore area. \"Although middle-income families have declined considerably as a share of the overall family income distribution, it is noteworthy that middle-class neighborhoods have disappeared even faster in metropolitan areas, especially in cities,\" the study reports.