Numbers Bring a Reporter to Empty, but Not Vacant, Pieds-à-Terre

New York real estate is constantly changing, and it’s always a source of fascination. Julie Satow, a contributor to the Real Estate section, describes how tracking statistics uncovered a story about high-end New York City neighborhoods that are virtually uninhabited.

There is a statistic that has been bandied about in various news articles discussing the increasing number of pieds-à-terre in New York City’s luxury condominium buildings. It says that in one area of the Upper East Side, 30 percent of the apartments are vacant at least 10 months a year. I called the Census Bureau to track this figure down.

Turns out, this number is several years old. But a spokeswoman showed me how to find the most recent figures, dating from 2012. These numbers, gathered by census takers who sent mail, called and then repeatedly went to the apartments to track down owners, is easily accessible on the Census Bureau website. Playing around, I was able to identify neighborhoods where nearly 60 percent of the apartments were vacant the majority of the year.

But the census data didn’t divulge the vacancy rates of specific buildings. I asked James Parrott, an economist who follows the issue, whether there was any way to drill down further. He said it would be possible to look at specific apartments and see whether the owners were receiving a tax break that is available only to primary residents. It is a tricky, time-consuming process that includes searching the city’s Department of Finance database.

So I called the Independent Budget Office and asked them if they could run the numbers for a handful of buildings. They obliged and are now looking to apply this methodology on a much wider scale across the entire city.