Background checks decreased 10 percent nationally between December and January, with large declines in the Southern states of Alabama, Arkansas, Louisiana, Mississippi, Tennessee and Virginia as well as Texas, according to an Associated Press analysis of new FBI data published Tuesday.

Firearms sales surged around the country after the December shooting spree in Newtown, Conn. A gunman killed 20 children and six adults at the school.

There were more than 2.78 million checks in December. That was a 12-month peak following an upward trend through last fall. The number fell to 2.48 million in January, still a higher figure than any other month than December last year.

“You can’t do a background check if a guy doesn’t have a gun to buy,” said Mike Fotia, manager at Duke’s Sport Shop in New Castle, Pa. “There’s nothing to buy.”

Fotia said manufacturers and wholesalers can’t fill orders right now because demand is so high.

Gun sales traditionally dip after the rush of the holiday shopping season, and the decrease this year is the smallest since 1998 when the federal government began tracking federally mandated National Instant Criminal Background Checks. This year’s smaller decrease confirms what gun-sellers have reported seeing: There continues to be a higher interest in firearms than in previous years, but there have been fewer buyers recently because gun stores are out of stock.

“Availability has been an issue. You’re just not able to sell as much,” said Katie Stulce who owns Champion Firearms Corp. in College Station, Texas. “We’re probably turning away 60 percent of the people coming in wanting to buy something.”

The number of background checks does not necessarily represent the number of firearms purchased, but gunmanufacturers use these statistics to measure the health of the gun industry in the U.S.

Louisiana, Alabama and Mississippi saw the largest declines in background checks from December to January, by nearly one-third. Those states also saw some of the highest increases in background checks between November and December last year.

Even before the Newtown shooting massacre and pledges from the White House to curb gun violence with new laws, the gun industry was experiencing a boom in sales. Manufacturers couldn’t keep up with demand. After Newtown, gun sales went up even more. People in the gun business called the rush to buy guns after the Newtown shooting a “banic,” meaning people are panicked President Barack Obama would ban guns, said Bill Bernstein, owner of the East Side Gun Shop in Nashville, Tenn.

The FBI conducted more background checks for firearm sales and permits to carry guns the week following the Newtown shooting than it has in any other one-week period since 1998. The second-highest week for background checks came mid-January as Obama announced sweeping plans to curb gun violence.

Bernstein said that rush changed for him about two weeks ago, when business started to slow. Background checks decreased by 24 percent between December and January in Tennessee, while checks went up by 53 percent there between November and December. Bernstein said sales in his store went down 23 percent between December and January.

“It felt like somebody just flipped a switch,” Bernstein said. “One day I had the shop filled with people, the phone ringing off the hook. The next day, hardly anything.”