Most Democrats want stricter gun laws, and most Republicans oppose them. So you might expect the election of Donald Trump and a Republican-controlled Congress to be great news for the nation’s gunmakers. But surprisingly, the opposite turned out to be the case.

Two of the nation’s biggest gun manufacturers, Smith & Wesson and Sturm Ruger, saw their stock prices fall by double digits this morning in the wake of Trump’s election victory.

Here’s one theory for what’s going on: In recent years, gun sales have been driven by fears of gun confiscations. Gun sales soared after Obama’s election in 2008 and again when he was reelected in 2012, as people worried that the president would begin to confiscate the nation’s firearms.

In contrast, gun owners have little to fear from a Trump presidency or a Republican Congress. So gunmakers are likely to make fewer sales over the next four years.