New York's hottest, most exclusive neighborhood is Rikers Island. Julie Zeveloff/Business Insider The most expensive neighborhood in New York City isn't TriBeCa or the West Village. It's Rikers Island.

The city spent an average of $167,000 per inmate on its jail system in 2012, according to a new report from the city's Independent Budget Office. That's nearly three times the cost of New York State's prison system and five times as much as the national average, according to data from the Vera Center for Justice and the Pew Center on the States.

Doug Turetsky, communications director for the IBO, said the agency has not looked in detail at why the city's jails are so expensive. But the New York Times reports that 83% of jail costs go to employee wages and benefits, and that New York City has unusually high staffing ratios in its jails.

There is a silver lining: the city's jail population has declined massively over the last two decades. New Yorkers are significantly less likely to be incarcerated than the national average.