I think Jason Vorhees has killed roughly the population of Vermont across all of his films, and that seems extreme at best. Every attempt to stop Jason has failed miserably. The closest anyone came to pulling it off was cryogenic freezing -- which amounted to nothing, since not only did they thaw him out and make him stronger, but the filmmakers also just went ahead and kept making movies about him set in the present anyway. He's been to hell and space now; all that's left is Detroit, and maybe North Korea.
Of all the ways Jason has murdered people across his films -- of which there are exactly 417 now -- the all-time best is this one. The sleeping bag beating.
People might tell you that Jason's greatest kill is the liquid nitrogen kill from Jason X, in which he freezes a woman's face and then shatters it. That cannot be his greatest kill, and this isn't even an objective argument, because it takes place in Jason X. The one in space. I mean, seriously. Get fucked, space sequels.