After a teenager on Wednesday slaughtered at least 17 people in Marjory Stoneman Douglas High School in Parkland, Fla., the share prices of gun manufacturers went up.

American Outdoor Brands Corporation (AOBC), the maker of Smith & Wesson guns, saw its share price rise by 5.6%. Sturm, Ruger & Company (RGR) was up 2.8%, ammunition and rifle-scope firm Vista Outdoor (VSTO) was up 2.8%, and ammunition maker Olin (OLN) was up 1.4%.

This has become a familiar sight in the aftermath of mass shootings, with likely reasons including the anticipation of more people buying guns to defend themselves, and the possibility that buyers might fear an impending crackdown on gun ownership, leading them to buy new firearms sooner rather than later.

The same thing happened after last year’s deadly Las Vegas shooting spree.

Read: Trump Says Texas Church Shooting Is Due to ‘Mental Health Problem’—Not ‘a Guns Situation’

That said, gun manufacturers have not been having the best of times under Donald Trump’s presidency. The so-called “Trump Slump”—where some people no longer feel the need to make a political statement against a relatively anti-gun White House by buying guns—was one factor cited in the recent Remington bankruptcy.

American Outdoor Brands saw its profits reduced by 90% last year, while Sturm Ruger said in October that its quarterly profits were down 35%.

The gun used in the Florida shooting is reported to have been an AR-15 assault rifle.