A Timeline of School Shootings Since Columbine by Marco Giannini

On April 20, 1999, the United States where shocked by the High School school shooting and attempted bombing in Columbine, CO. It caused 15 fatalities (12 students, one teacher, and two perpetrators) and 21 injuries in just an hour with guns, ammunition, and homemade bombs. While this was not the first instance of a school shooting, it got a great deal of media coverage. Despite harsh criticisms to violence intrinsic with the American society, numerous documentaries about Columbine, and school safety training efforts for both students and teachers, the problem of school shootings has only grown more and more prominent since then.

School shooting is now such a usual accident that the news coverage of these events mutated, from tons of press releases regarding the Columbine massacre and some of the latest shootings barely getting a short piece on local newspapers.
Is the big audience becoming accostumed to school shootings? How many of them have there been since Columbine, and how many of them have drew no notice at all?
This infographic visualizes the There have been 229 U.S. school shootings since 1999’s Columbine massacre. It does not include misfires or violent attempts stopped before being executed.

The entrant has supplied multiple files for this work:

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