Some great info from the author who sold 44, 334 Kindle books in December. The vast majority of these sales come from three 74p books. He has two other novels on Kindle. "Bangkok Bob and the Missing Mormon, which sold 302 copies, and Private Dancer, which sold 205 copies. Why are they so far behind the other three? Because I am selling them at full price."
Price is a huge factor, no question. Still, when you look at Bookscan figures (print sales) for most authors outside the bestsellers, selling over 500 copies of full-price novels in a month isn't to be sneezed at. And of course Stephen Leather's getting 70% royalties on each sale. In terms of money in an author's pocket, that's roughly the equivalent of selling 50,000 mass market paperbacks. And I'm betting Leather will hit similar sales figures (if not better) next month, and the month after, and the month after.