The 2010 Census came under scrutiny in March after it found that 10,000 people left Astoria, that Queens had only grown by 0.1 percent since 2000, that roughly 12 percent of blacks left Manhattan to go to Staten Island, and more. The general consensus among New Yorkers was that the numbers don't seem accurate, and on Monday, a City Council committee hearing was organized to try to figure out what happened, and what can be done to correct it. But while several theories were proposed as to why the numbers don't seem to add up, each of them leaves much to be desired.

Tony Farthing, the director of the New York region of the Census Bureau, was the first to give his testimony. He claimed that there were many reasons why the Census could be inaccurate, ranging from people refusing to participate to doormen being reluctant to allow Census workers into apartment buildings. Although common Census practice is to try knocking on a door a maximum of six times before labeling it vacant, an exception was made in New York, where additional visits proved fruitful on several occasions. Unfortunately, there were other occasions when returning more than six times resulted in threats against the Census workers, in which case the house was labeled as having only one person living in it.

Another explanation for the oddities in the Census Bureau's data was illegal subdivisions of housing. For example, if a person is illegally subletting his house to a family and actually lives with eight people, he is not likely to admit this to a Census worker. He would either lie about how many people he lives with, in which case the data is incorrect, or he would not bother answering the door at all, in which case his house gets counted as vacant despite the nine people living there.

Councilwoman Diana Reyna theorized that "hipsters" may be part of the cause for the inconsistency of the census numbers, stating that some of them "only want to be counted in their home state," and that they might not participate in the Census because it wouldn't be "cool."

Another possible reason for the apparent undercount: illegal immigrants who are simply too afraid to talk to the government. (It's also possible that people did leave New York for economic reasons and that the undercount is actually not that far "under.")

According to Farthing, the Census process is still incomplete. Now that the numbers are in, Count Question Resolution (CQR) forms are available. A CQR is a form on which the highest elected or appointed official of state, local, and tribal area government can challenge the census.

"In the best case scenario, we submit our requests, and then in a few weeks or months, the Census Bureau says they made a mistake, say that it was a coding error, and fix it," said Joseph Salvo, the Director of the Department of City Planning's Population Division.

But if the problem is not in how the data is processed, but in the data itself, New York may have to settle for the current count. Only processing errors can be remedied after the numbers become official, which greatly limits a CQR's effectiveness. In other words, if a site has been falsely labeled as vacant, only to have it emerge that it is not, the vacancy cannot be deleted. It can only be modified to show that there are people living there, if there are. Drastic changes such as deletions were virtually impossible, Farthing said.

Councilman Vincent Gentile questioned the usefulness of this system, asking what good it was to work with current data if the data is incorrect. "There are going to be a tremendous amount of undeleted vacancies," Gentile said. "And therein lies the problem."

When Gentile suggested that the Census Bureau create another category for houses that are unverified vacancies (as opposed to just labeling them vacant), Farthing said that this might be implemented--during the 2020 Census.