According to a new StreetEasy research, one in every four of the more than 16,200 condo units erected in New York City since 2013 remains unsold, or around 4,100 apartments, the majority of which are in premium buildings. There were about 5 million square feet of space under construction at the end of 2017, according to data from CoStar. The number of unsold condos has increased over time. In 2013, there were 3,000 unsold units; by 2016, this number had risen to 4,100; and as of September 2018, there were 6,400 unsold units. There are several reasons why so many condos remain unsold. Some people prefer to rent rather than buy, while others may not be able to afford buying a home. In addition, poor sales have kept builders from putting up more units, while high prices have prevented other people from moving into already available spaces. New York City is a place where people want a yard, a house, or at least an apartment with a garden or patio. It's also known for its expensive real estate market. While most cities across America are experiencing a shortage of housing, this isn't the case here. There are too many houses on the market that aren't getting sold and too few buyers to go around.