Just 3 percent of adults in the United States own half of the country’s guns, according to a new study by researchers at Harvard and Northeastern universities.
An estimated 7.7 million adults nationwide make up a group of so-called gun super-owners, stockpiling anywhere from eight firearms per person up to 140. On average, they own 17 guns apiece, researchers said.
On the other end of the spectrum, half of the estimated 55 million gun owners in America own either one or two guns, according to the study.
The paper’s lead author, Deborah Azrael, director of research at the Harvard Injury Control Research Center, said that from a public health perspective, she was most intrigued by that group.
Azrael, in a phone interview with the Globe on Tuesday, said that better understanding how people in that larger cohort store their guns could potentially reduce suicides by gun.
“It’s possible to imagine talking to those people about the risks and benefits of guns and to help them think of whether having a handgun ready for immediate use confers more benefit or not,” she said.
Nearly two-thirds of the 30,000-plus gun deaths in the United States each year are suicides.
The most common method of suicide in the United States is by firearm, and researchers have found that people who live in a household with a gun are more likely to kill themselves than people who don’t. Suicides are often impulsive acts, researchers say.
The Harvard-Northeastern study found that the percentage of Americans who own a gun at all has decreased slightly between 1994 and 2015, from about 25 percent to 22 percent.
But the total number of guns owned in the country increased during that same time by about 38 percent, or 73 million guns, to an estimated 265 million guns — a figure that outnumbers the 242 million adults living in the United States.
The study found a particularly sharp increase in the number of handguns. There were an estimated 111 million nationwide in 2015, a 71 percent increase from the 65 million handguns estimated in 1994.
Researchers said that the growing popularity of handguns coincides with the rise in people owning firearms — and in particular handguns — for self defense.
Nearly two-thirds of gun owners told researchers that protection against other people was one of the primary reasons they own a gun, making it the most commonly cited reason for ownership.
The trend was somewhat puzzling to researchers given how, even though the gun homicide rate is much higher in the United States than in other developed countries, the rate has declined significantly nationwide since the early 1990s.
Azrael said that, to her, the central question is: “Who are they protecting themselves from?”
“What is creating this sense that they have a need for protection, particularly in a world where the actuarial risk of victimization is low?” she said.
Azrael said part of what may be stoking people’s fears is marketing by the gun industry.
“There have been pretty big efforts to convince consumers that they need guns for protection,” she said.
The study also looked at demographic trends of gun ownership, including finding that the proportion of women who said they own a gun has increased.
The study was based on a survey of nearly 4,000 adults, researchers said.
The study has not yet been published. The full results of the study are undergoing peer review and are due to be released next fall by the Russell Sage Foundation.
The Guardian and the Trace reported that some people who own relatively large numbers of guns said they were dedicated collectors, firearms instructors, gunsmiths, hunters, or competitive shooters. Others said they were stockpiling the weapons, along with food and water, in case of disaster.
Still others said they had simply acquired guns in small numbers over a period of time — including some inherited from parents and grandparents — and wound up with a relatively large total, according to the Guardian and the Trace.
By Matt Rocheleau GLOBE STAFF