(WAFF) - Charleston. Chattanooga. Lafayette. Roseburg, Oregon. Colorado Springs.
Now, San Bernardino.
Six cities, all torn apart by deadly mass shootings.
The website Mass Shooting Tracker defines a mass shooting as, "an incident in which at least four people are killed or injured by gunshot."
Based off that definition, there have been 352 mass shootings in the last 336 days of 2015.
The FBI has a more conservative definition for a mass shooting. They label active shooter incidents as "an individual actively engaged in killing or attempting to kill people in a confined and populated area."
Based on that definition, there have been 160 active shooter incidents between 2000 to 2013.
That breaks down to 1,043 casualties, and averages out to a little more than 11 mass shootings a year.
According to the FBI, mass shootings have been steadily increasing since 2000.
The FBI says mass shootings are most likely to take place in some type of business. That's followed by a school or a church, and then in a government agency.
Click here for their full report.