Is NYC expensive for New Yorkers?

When you take the salary of an average (not wealthy or poor, but middle class) New Yorker living in the heart of the city into account, is it even enough to not only pay rent (on top of a deposit in advance for first time renters) including bills utilities, internet, maintainence fees or muncipality fees & not forgetting food on the table. I've heard that NYC has the reputation of being the most expensive in the globe. Is that true?