Hmmmm, I think you're looking at that table wrong. Ten titles sold between 500,000 and one million copies (not 5-10 million copies). And 267 titles sold between 100,000 and 500,000 copies, (not in the millions). That top line is the highest one.
(I really enjoyed the article, by the way, once it was past claims about this data-- the points about fanfic and story monetization are important ones)