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why are you asking me? you could google it - and you'll find the answer in about 500 different places.

https://www.usatoday.com/story/news/nation-now/2018/02/15/australia-hasnt-had-fatal-mass-shooting-since-1996-heres-what-did/340345002/

I was asking you because those 500 different places would have 500 different definitions.

Yet not one of those definitions would have the United States faring better than Australia