Summary
Active shooter incidents in the United States (US) increased an average of 27% per year from 2000 to 2020. These 21 years experienced 570% net growth, beginning with 3 active shooter events in 2000 and growing to 40 in 2020. In this article, we use Federal Bureau of Investigation (FBI) source data to chart yearly growth using the Average Annual Growth Rate method.
Definitions
In short, an “active shooter” is defined by the US government as “an individual actively engaged in killing or attempting to kill people in a confined and populated area”. The use of a firearm is implied, but not explicitly stated. For more detailed explanations of "active shooter" and "mass shooting", please see, "What is an Active Shooter?" and "What is a Mass Shooting?".
Data Source
How the data was analyzed
Change From Prior Year Formula: (Year2 Events / Year1 Events) - 1 = % Change.
Example: ( 10 [Year 2001 Events] /3 [Year 2000 Events] ) -1 = 233%.
Average Annual Growth Rate (AAGR) Formula: ( % Change1 + % Change2 + ... ) / Years = AAGR
Example: ( 0% + 233% + ( - 30% ) + 71% + ( - 58% ) + 120% + 9% + 17% + ( - 36% ) + 111% + 42% + ( - 52% ) + 62% + ( - 10% ) + 5% + 0% + 0% + 55% + ( - 3% ) + 0% + 33% ) / 21 Years = 570% / 21 Years = 27% AAGR.
Where can I find more resources on this topic?
If you would like to learn more, you can request a list of highly-reputable resources here. We regularly review new material to keep our holdings current. If you know of good resources not already listed, please let us know.