I just updated my spreadsheet to include the St. Cloud Mall stabbings, and this incident. I also stumbled across a theater shooting in Lafayette, LA, in July of 2015 that I didn't know about. I'm certain I've missed more than one, but I spent a lot of time on-line looking for mass killings, and I entered every one I could find going all the way back to 1784.
Some interesting statistics come out of this. The Democrats are gung-ho to ban so-called "assault" weapons, but they're also all in favor of admitting Muslims from terrorist hotbeds into the U.S. So take a look at these numbers:
Total number killed in mass murder type incidents: 3,724. Number killed by "assault" weapons: 122 (3.28%). Number killed by Muslim terrorists: 3,056 (82.06%).
Total number wounded/injured in mass murder type incidents: 7,528. Number wounded/injured by "assault" weapons: 155 (2.06%). Number wounded/injured by Muslim terrorists: 6,406 (85.10%).
I think the Democrats have their priorities misaligned.