Both sides of the gun control debate saw this week’s decisions by Dick’s Sporting Goods, Walmart and Kroger to limit firearms sales as symbolically game-changing.
But whether those changes will actually have a meaningful effect on gun sales is difficult — if not impossible — to know.
In an era when the toy industry can pinpoint the overall value of all dolls sold domestically each year and the federal government tracks the number of trucks sold in any given month, data on gun sales is obscured by foggy reporting standards and loopholes. There is no nationwide registry that tracks gun ownership while firearms are available to purchase from a decentralized network of retailers, shows and individuals that operate publicly, privately, online and offline.
Many trade groups can offer granular detail on the products their members manufacture, but the gun industry is much less forthcoming. Only a handful of gunmakers are publicly owned and required to provide some sales information.
Efforts to require a nationwide registry have also faced resistance over concerns about potential threats to Second Amendment rights — a central repository of data could eventually lead to firearms being confiscated by the government, critics have said.
Some researchers have blamed the National Rifle Association, the firearms industry’s powerful lobbying group, for blocking the government’s ability to study guns and gun crimes. For example, a 1996 provision known as the Dickey Amendment effectively barred the Centers for Disease Control from tapping taxpayer funds set aside for injury prevention and control for research that could be used for gun control advocacy. For years, the stipulation severely chilled the C.D.C.’s activity in the field — even after 2013, when President Barack Obama ordered the agency to look into causes of gun violence and strategies to end it.
Gun control advocates believe that the lack of information is a way for the firearms lobby to skirt accountability for gun-related crime.
“The tracking of information in this industry is just not granular enough to be useful for policy discussions,” said David Chipman, a senior policy adviser at Giffords, a gun safety advocacy organization. “Tracking a gun is harder than tracking a package — you know at a high level how many firearms are manufactured, but you don’t know where they went from there.”
The end result is an industry that sees its numbers recorded only in broad strokes, and fewer of those strokes in each step of the way from manufacturer to retailer to buyer to second owner.
American gun manufacturers produce millions of firearms annually — nearly 9.4 million in 2015, according to the Bureau of Alcohol, Tobacco, Firearms and Explosives. Nearly 3.7 million of those were rifles, including AR-15-style semiautomatic rifles like those used in several mass shootings.
Only a few of the thousands of licensed firearms manufacturers in the country are publicly owned and must disclose sales figures to investors. Those include American Outdoor Brands Corporation, formerly known as Smith & Wesson Holding Corporation, which has reported declines in firearms sales for the past four quarters but generally does not report specific volumes. On Thursday, the company said that revenue from its firearms segment for the third quarter slumped 40.6 percent from last year to $117.6 million, compared with a 13.4 percent upswing in its outdoor products division.
Sturm Ruger, another public company, cut its production levels by 24 percent last year and also laid off 28 percent of its employees, according to Wedbush analysts. Other investor-owned businesses include Vista Outdoor and Olin, which both make ammunition.
A slew of smaller, single-product manufacturers emerged during the Obama administration, experts said. Most make semiautomatic firearms like the AR-15 known by some as assault weapons and by others as modern sport rifles. Few, if any, are eager to share performance metrics with the public.
And few gun dealers publicly disclose how many guns they sell. The N.R.A. did not respond to requests for information about sales.
Analysts estimate that fewer than a quarter of firearms sales to consumers come from big-box retailers like Walmart and the outdoor and hunting outfitter Cabela’s. At Dick’s Sporting Goods, revenue from hunting products, including rifles, constitute 10 percent or less of annual sales, according to another Wedbush report.
Although Dick’s stores can be found nationwide, it sold assault-style rifles only at its 35 Field & Stream stores and on its websites. Walmart, which had already instituted similar restrictions in 2015, sells firearms at about half of its nearly 4,000 supercenter locations nationwide.
Mom-and-pop shops make up a sizable percentage of the 56,000 federally licensed firearms dealers that the A.T.F. said were in business late last year.
Gun and ammunition stores in the United States did $8.6 billion in business in 2016, not including sales from sporting goods and outdoor stores, online retailers, gun show vendors and pawn shops, according to a report from IBISWorld. But shops are not required to regularly share inventory accounts, meaning it is unclear how much of that business is made up of assault-style rifles like those that Dick’s stopped selling.
There is a way to get a partial picture of retail gun sales from the National Instant Criminal Background Check System, which was established by the F.B.I. in 1998. But that system, too, lacks detailed data.
Federally licensed dealers cannot sell firearms without running a background check of the prospective buyer. But the due diligence process, which is conducted via phone or computer and usually completed within minutes, likely underestimates the true volume of gun sales. Requests for a background check do not disclose how many guns are being purchased in that transaction.
Licensed gun dealers are frequent fixtures at the thousands of gun shows that take place across the country each year, but private sellers, who are not required to run background checks on buyers, also attend the events. They often advertise personal firearms on signs strung around their necks, taped to gun cases or attached to rifles slung over their shoulders.
This so-called gun show loophole, which also applies to mail-order purchases and other transactions, allows firearms deals between individuals in the same state to go essentially unmonitored.
Research into such sales is limited. One A.T.F. study, from 1999, estimated that 25 percent to 50 percent of gun-show vendors were unlicensed. A study last year found that 22 percent of gun owners who recently acquired firearms had done so without a background check.