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For the past two decades new yorkers have been the beneficiaries of the largest and longest sustained drop in street crime ever experienced by a big city in the developed world. In less than a generation, rates of several common crimes that inspire public fear—homicide, robbery and burglary—dropped by more than 80 percent. By 2009 the homicide rate was lower than it had been in 1961. The risk of being robbed was less than one sixth of its 1990 level, and the risk of car theft had declined to one sixteenth.