What’s an unaffordability map? Well, it’s what came out of a special request from the Gothamist editorial team, who wanted to see which neighborhoods are gentrifying the fastest. By measuring the median home sale price in each census tract, divided by the median household income, the map highlights which neighborhoods in the city’s five boroughs are the most expensive, in areas where most people aren’t currently earning that much. Take a look at our dynamic map, and search for the dark purple markings—that highlight neighborhoods like East Williamsburg where homeowners are paying high prices for their units, despite the fact that most people in the neighborhood are not what you would call top earners. While elevated prices in neighborhoods like NoLita, Prospect Lefferts Gardens, and Sunset Park are somewhat easier to explain, the areas along Kissena and Parsons Boulevards in Flushing also seem to be gentrifying at a surprisingly fast pace. For further details, check out Gothamist’s coverage of how our unaffordability map identifies the fast gentrifying neighborhoods of NYC. Census tracts were used to compile the data, with residential sales priced over $50,000 that closed in 2012 and 2013. To get an accurate median sale price, we only looked at census tracts that had 4 or more sales, the gray areas on the map representing either rentals or other commercial properties not included in the report.