I feel like people doing word counts to try and compare artists my metrics have the wrong idea.
Harry Potter and A Song of Ice and Fire are vastly different kinds of stories.
Harry Potter is entirely from the perspective of one character, aside from one or two chapters, and Rowling has to deal with a few other factions operating 'outside the page' (meaning Order of the Pheonx, Voldemort's Death Eaters, and the Teachers of Hogwarts, unless I'm forgetting someone) while they write. GRRM has 8 or more point of view characters at any given book, who are all going their own separate storyline (except for Game of Thrones, where Ned and his family were all basically together through the work) In addition to that, he has literally dozens of factions he has to keep an eye on. And he has to tie all that together into something resembling a cohesive narrative. In addition to that, he's also doing other projects. For example, does that graph count the Dunk and Egg short stories he wrote? Or the History book?
Plus, regardless of what you think of quality, when you get down to it, not all writers work the same way. Some can make a draft, go through 2 or 3 revisions, and boom, done. Brandon Sanderson seems to work this way. Other writers, which George seems to be, revise a dozen times over. Since someone mentioned Rothfuss, from interviews, he revised his novella literally 80 times before he was satisfied with it, and that was on the light side for him. I think he mentioned Name of the Wind and Wise Man's fear got 120+ revisions.
Sorry, but it just seems so stupid. I don't try to aggrandize the writing process at all, because it's work and you just sit your ass down and do it. For some people, sitting their asses down and doing it means 5 years. And as long as he's actually doing it, which isn't information any of us are privy to unless we know him personally, I just can't get over people complaining about him being lazy.