How many mass shootings have there been in 2015?

The violence that killed sixteen and injured 21 in San Bernardino today was the day’s second mass shooting. The first, an attack that left one dead and three injured in Savannah, was largely overlooked, due to the scope of the shooting in California. But a day with multiple mass shootings is hardly irregular–there have been dozens of them so far in 2015.

How many mass shootings have there been in 2015 in total? According to the carefully maintained Mass Shooting Tracker wiki, the answer is greater than the number of days to this point in the year. Mass Shooting Tracker–and its affiliate, the GunsAreCool forum on Reddit–count 355 mass shootings in the United States as of Tuesday, December 2nd. December 2nd is the 336th day of the year.

(It’s worth pointing out that “GunsAreCool” is an ironic name; the administrator of the forum is a survivor of gun violence and an advocate for gun law reform.)

How does the group define a mass shooting? Its Reddit page offers a lengthy and detailed explanation of both the definition and that definition’s justification; what it boils down to is that a shooting becomes “mass” and is added to the tally when “four or more people are shot in a spree or setting, likely without a cooling off period.” That figure can include the gunman.

Mass Shooting Tracker arrived at its measuring stick by updating the “old” FBI definition, which only counted four or more murders–and not every victim of a fired shot–at one time. “Because ‘shooting’ means ‘people shot,'” the explanation reads, “it is therefore only logical that a Mass Shooting is four or more people shot in one event.”

The group suggests that counting all victims of gun violence, instead of only those killed by such violence, amounts to a strike against the gun lobby, which “benefits from our ability to save those who would otherwise die, even though those gun shot victims are still just as shot and will never be the same.” In the words of GunsAreCool, “The NRA evades the gigantic costs of gun injuries to society and shifts the burden to taxpayers who often pay the costs for the medical care of the wounded.”

As for the number of American mass shootings in previous years, Mass Shooting Tracker tallied 336 last year, and 365 in 2013.

A related Washington Post calendar also helps to illustrate the frequency with which mass shootings occur in America. (We can’t show you the graphic in the article, but you can click this link to see it.) A few noteworthy facts about mass shootings in America in 2015:

-As of this writing, 2015 has seen 81 days with more than one mass shooting. With 336 days gone in the year, the chance of two or mass shootings taking place in one day is one in four.
-Only one month in 2015–February–has had more days without mass shootings (15) than days with (13). October came close; it had 15 days without mass shootings, and 16 with.
-To date, the longest stretch of days without a mass shooting is 8, from April 8th to April 15th.
-The most common day for mass shootings in 2015–by far–is Sunday. Of the year’s 48 Sundays to this point, 38 have had a mass shooting.
-The highest number of mass shootings in a single day (so far) is five. To date, America has seen five shootings take place five times this year: on April 18th; June 13th; July 15th; August 2nd; and November 22nd.
-To date, the month with the highest percentage of mass-shooting days is June. Mass shootings did not take place on only four days (or 13.3%) this past June, meaning that, on twenty-six of thirty days (86.7%), they did.

 

Further reading: GunsAreCool Reddit forum
Mass Shooting Calendar Graphic (through December 2nd, 2015)

 

(Photo credits: Mass shooting figures one, two, three via Flickr)