A study on mass shootings in developed countries showed that 101 out of 139 attacks took place in the US between 1998 and 2019, leading to 816 deaths. The US accounts for 73 percent of 139 mass shootings that occurred in developed countries between 1998 to 2019, according to a new study. Published in the International Journal of Comparative and Applied Criminal Justice, the study compared mass shootings in the ...