Mass shootings in the United States

Mass shootings are events where there are many victims of firearm-related violence. There is no exact definition for a "mass shooting". One definition is that a mass shooting is an act of public firearm violence in which a shooter kills at least four victims. Gang killings, domestic violence, or terrorist acts by an organization are not included. With this definition, one study found that about one-third of the world's public mass shootings between 1966 and 2012 (90 of 292 events) happened in the United States. "The Washington Post" recorded 163 mass shootings in the United States between 1967 and June 2019.
Statistics.
The United States has had more mass shootings than any other country. Shooters generally either die by suicide afterward, are arrested, or are killed by police officers or civilians.
Mass shootings are responsible for under 0.2% of homicides in the country between 2000 and 2016.
According to a March 2022 report, over mass shootings in the last 40 years, in 52% of mass shootings in the United States the shooter was white, 16% were African American, and 8% were Latino. In 96% of mass shootings the shooter was male, in 2% they were female, and in 2% there were both male and female shooters.
Weapons used.
Many types of guns have been used in mass shootings in the United States, including semi-automatic handguns, semi-automatic rifles, revolvers, and shotguns. Of the 172 events from 1966 to 2019 that are seen as mass public shootings in the U.S., handguns were used in 77.2% of cases and semi-automatic rifles in 25.1% of cases. From 1966 to 2019, about 77% of mass shooters in the U.S. legally bought the weapons used in the attacks.
Mental health.
In a study, experts said that roughly one-third of acts of mass shootings since the 1990s were committed by people with a "serious mental illness". However, the study also said that people with a serious mental illness are responsible for less than 4% of all the violent acts in the United States. The American Psychiatric Association (APA) said that gun violence is a public health crisis and that a majority of people with mental illness are not violent and "are far more likely to be victims of violent crime." 
In February 2021, a survey published by psychiatrists at Columbia University found that in 1,315 out of 14,785 mass murders around the world, personal motives were the main cause. In only 11% of these 1,315 murders and 8% of these shootings, the murderer had a serious mental illness.