This might be a stupid question, and I know PR is outdated. But what does a -1 PR mean for a site? Is it an indication of some kind of penalty or something? Or could it be that the site has been de-indexed? My last thought is if it could be because the site was created after the last PR update, and has therefore not gotten a PR value assigned to it, so therefore it wouldn't mean aything? I tried searching for it, but just found posts saying that "it's a bug" or "there is no such thing as PR -1"