Mass shootings are defined as events in which four or more people, excluding the shooter, are shot, but not necessarily killed, at the same general time and location. Other definitions of mass shootings exclude certain shootings, such as gang-related and domestic events.

So far in 2019, 294 people have been killed and 1093 wounded in 266 mass shootings in the US.

At least 10 people, including the attacker, were killed, and another 16 were injured during a shooting on Sunday in Dayton, Ohio.

The attack came less than a day after another gunman opened fire in the Walmart Cielo Vista Mall in the city of El Paso, Texas. Twenty people were killed and 26 more were injured, many of whom remain in critical condition.

On December 14, 2012, a gunman walked into Sandy Hook Elementary School in Newtown, Connecticut, and killed 20 children, six adults, and himself.

After Sandy Hook, 2191 mass shootings happened.

Since 2013, there has been only one full calendar week — the week of January 5, 2014 — without a mass shooting.

The longest respite was 11 days between January 8, 2013, and January 18, 2013, when no mass shootings were reported, according to the Gun Violence Archive.

By June 12, 2016, when a shooting at a nightclub in Orlando, Florida, led to 50 deaths, there had been 994 more shootings. Orlando was the deadliest mass shooting in modern US history until October 1, 2017, when a gunman fired into a crowd at a music festival on the Las Vegas strip, killing 59.

In 2016, according to the US health protection agency, 39,000 people died of gun-related injuries.

Mass shooting deaths represented less than 2 percent of all gun deaths in the US that year — 451 of nearly 39,000 overall gun deaths.

Meanwhile, more than 14,000 of the gun deaths that year were homicides, and almost 23,000 — the great majority — were suicides.

Then on February 14, 2018, a gunman opened fire at Marjory Stoneman Douglas High School in Parkland, Florida, killing 17.

In total, there have been at least 2,191 mass shootings since Sandy Hook, with at least 2,476 killed and 9,158 wounded, and almost no state is immune to mass gun violence.

It is worth to mention that the US is a big outlier among developed countries when it comes to gun deaths — in large part because it has so many guns – with 88.8 guns per 100 people- making it easy to carry out an act of violence.

As shocking as mass shootings are, they are responsible for only a small portion of all gun deaths.