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Story highlights

An estimated 251,000 people died by gun in 2016. In 1990, there were 209,000 firearm-related deaths

Gun deaths are mostly concentrated in six countries that account for less than 10% of the world's population

(CNN) —  

Mass shootings and acts of terrorism may dominate headlines, but it’s the homicides and, to a lesser extent, the suicides that happen out of the spotlight that make up the bulk of firearm-related deaths around the world, according to a study published Tuesday in the journal JAMA.

More gun deaths happened outside of war than in it during the years researchers examined (1990 through 2016) in 195 countries and territories.

Worldwide, an estimated 251,000 people died by gun in 2016. In 1990, there were 209,000 firearm-related deaths. Accounting for population growth, that’s an annualized rate decrease of 0.9%.

Gun deaths are predominantly concentrated in six countries that make up less than 10% of the world’s population. The United States, Brazil, Mexico, Colombia, Venezuela and Guatemala together account for more than half of the gun-related deaths worldwide.

In 2016, the majority of global firearm deaths – an estimated 64% – were homicides. Suicides accounted for 27% of the gun deaths. A small fraction, about 9% of gun deaths, were accidental.

If you were to look on a map, the highest numbers of gun-related homicides are concentrated in a belt that stretches from Mexico through the Caribbean to Brazil. Many of these homicides involve drug cartels, the authors suggest, and there’s a problem with organized crime and the illegal gun trade.

El Salvador saw the greatest concentration of gun-related homicides in 2016, with 38.9 per 100,000 people. By comparison, Singapore, the country that had the fewest, had 0.1 gun-related homicides per 100,000.

“The sheer magnitude of these deaths and the range in firearm-related deaths is extraordinary,” said the study’s senior author, Chris Murray, director of the Institute for Health Metrics and Evaluation at the University of Washington.

The most vulnerable demographic to gun violence was men between 20 and 24 years old. Men were also the biggest perpetrators of gun violence.

Suicide-by-gun rates declined globally between 1990 and 2016. Some countries, though, struggled with this public health crisis. In 2016, Greenland had the highest number of firearm suicides, with 22 deaths per 100,000 people. The US had the second-highest number, with 6.4 deaths per 100,000 in 2016.

“The US really has quite marked rates around suicide,” Murray said. “That was a surprise to me.”

For perspective, the United States has 4.3% of the world’s population, but suicide by gun there represented 35.3% of all firearm suicides in the world in 2016. By comparison, there were twice as many firearm suicides as gun-related homicides in 2016 in the US.

Americans also own more guns per capita than residents of any other country, with about four in 10 Americans saying they either own a gun or live in a home with guns, according to a 2017 Pew Center study.

Americans have been killing themselves more with guns over the past decade, but homicide numbers have been relatively flat. The US ranks 30th in the world for total number of homicides, according to the study.

The highest increase in gun-related suicide rates in this time period was in Jamaica, and Singapore had the fewest gun-related suicide deaths. These numbers, Murray said, are an important reminder about how widespread this public health problem is.

There is no one single trend behind gun violence. Drugs, alcohol, a lack of mental health services and domestic violence are often to blame, as is poverty, the study suggests.

“Places with high rates of firearm mortality that are getting worse tend to be places with weak government institutions, especially in the criminal justice system or social upheaval,” Daniel Webster, who has written extensively about gun violence as director of the Johns Hopkins Center for Gun Policy and Research, wrote in an email. Other things that stood out from these numbers, he said, is that while the “measures aren’t great,” he said, “there is a connection: more guns, more gun-related deaths.”

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Webster, who was not involved in the new research, added that the general downward trend in firearm mortality is something that stands out because “we tend to think of our current rates of gun violence as the worst ever, but there has been great progress” toward stemming some of this violence.

Laws that seem to limit gun violence include ones that strengthen background checks and require permits for ownership, the study authors said. More restrictions on guns in Brazil and South Africa seem to suggest a link between a reduced access to gun ownership and a lower number of gun-related suicides and homicides.