The FBI has released a study showing the mass shootings have become more frequent in the past seven years. From 2000 through 2006, there were an average of 6.4 mass shooting incidences a year. From 2007 to 2013, that increased to an average of 16.4 annual mass shooting incidences. The largest portion of the mass shootings, 45.6 percent, occurred in commercial settings, followed by 24.3 percent that took place in educational environments. In total, the mass shootings killed 486 and wounded 557 from 2000 to 2013.