Posted on May 9, 2016 by Amy Zimmer in DNAinfo DNAinfo, By Amy Zimmer Whether it’s a new glass tower going up or a beloved mom-and-pop shop closing down, locals often blame gentrification for unwanted changes in their neighborhoods. But what actually defines gentrification? NYU’s Furman Center, in a report released Monday, identified 15 neighborhoods that can be classified as “gentrifying” — areas that were relatively low-income in 1990, but then experienced higher rent growth in the following 20 years compared to other neighborhoods.