The New York City mayor's office announced this week that there have been 332 murders in the city so far in 2013, a number that would represent a 20 percent drop off from 2012, which was already a record-setting low. If the figure remains unchanged over the next two day, that would also be a 48 percent change since 2001, and a jaw-dropping 82 percent change since 1993, when the number of murders in the city was in the thousands.

That's a pretty good situation for William J. Bratton, Bill de Blasio's new police commissioner to be walking into. And further, the drop in murders this year coincides with another drop in stop and frisk encounters — down 60 percent through September, The New York Times's Andy Newman reports — suggesting that the controversial strategy has not contributed as much as it defenders have claimed.

New York is also not the only city to see big improvement Los Angeles, Philadelphia, and even Chicago (which has developed a reputation for out-of-control gun violence) all saw their murder rates decline in 2013, too. There isn't a clear explanation of what exactly has pushed New York City's murder rate so low, but there are several theories: Gun possession has fallen; new city's initiatives against gang violence; and the police squad's attention on "impact zones"— precincts where additional officers are assigned, have all contributed to the drop in murder and a overall drop in violent crime. 

Before New Yorkers can start patting themselves on the back, it would pay to keep in mind that this historically low 300+ figure would still be high in other places that aren't New York City. London, which has a population comparable to New York, saw just 99 murders last year.