Last weekend in Chicago, two people were killed and at least another 17 were wounded in shootings across the city. That violent outburst brought the city's homicide toll on the year to 146, according to the New York Times.

However, for all the tragic stories and headlines casting Chicago as the Deadliest City in America, the homicide rate in the Windy City is actually on pace to end the year at its lowest level since the the early 1960s.

Chicago has retained its stigma as a city with an out-of-control murder problem in part because of the shocking nature of the crimes. Many of the city's murders are gang-related, leading to a high number of youth casualties. In the most high-profile case of recent months, Hadiya Pendleton, a 15-year-old girl who had performed at President Obama's second inauguration, was shot and killed by a stray bullet in January.

Through the first four months of the year alone, there were 93 homicides in Chicago. But while that would seem to be a depressingly high tally, it was a 42 percent drop from the previous year. It also marked the first time since 1963 that there were fewer than 100 homicides over the same period.

Since then, the downward trend has continued. May saw an 8 percent decrease in homicides from the previous year, and a 31 percent reduction in total shootings. And through Sunday, there had been 76 fewer murders in Chicago this year than over the same stretch in 2012, a 34 percent decline.

Some have claimed that the local police, in trumpeting those striking comparisons, are cherry-picking data. Last year saw homicides spike to 506, their highest level in a decade, so the year-over-year comparisons are a little deceptive.

However, 2012 was something of an anomaly. The raw number of homicides in Chicago has been falling sharply since the early 1990s, according to data from the Chicago Police Department. In 1991, the city saw 928 murders; the next year, there were 943. But by 2004, the murder tally had dropped to just 453, and it's stayed roughly in that range ever since.

"These numbers are progress but they are by no means victory," Police Superintendent Garry McCarthy said in a statement last month.

Part of the downturn is the result of an expanded police presence, particularly in the city's more dangerous areas. Police said an effort to flood "hot zones" with more officers has led to the precipitous drop in the first few months of the year.

The city has also aggressively moved to pull guns from the streets. In May, Mayor Rahm Emanuel (D) announced that police had already confiscated some 2,500 illegal firearms this year.

It's also likely that Chicago's falling murder rate is reflective of a general downward trend in the nation as a whole. A preliminary analysis of crime data nationwide found that, through mid-May, the U.S. was on track to post its lowest murder rate since the turn of the century. Even if that pace doesn't hold up, Chicago's improving murder statistics over the past two decades still coincide nicely with a similar trend in the nation as a whole.

It's the type of empirical evidence that could weaken the arguments of gun-control advocates who claim the country's lax gun laws encourage gun violence.