New York, NY —

A new report finds that, even as New York City's population is growing, its middle-class is shrinking.

The think tank, Center for an Urban Future, says more people left the city for places like Philadelphia, Charlotte, even Allentown, in each of the years between 2002 and 2006 than in 1993, when the city was in far worse shape.

The Center's Jonathan Bowles says other cities are doing a better job of attracting industries that create middle-income jobs.

BOWLES: As jobs start being created in so many other cities before New York, I think that's what's going to open the floodgates for New York and it's going to prompt a lot of middle-class families that are unemployed or underemployed in New York City to leave and to go there.

REPORTER: Mayor Bloomberg acknowledges that more middle-class New Yorkers are leaving, but he says more middle-class people are coming.