Nielsen Bookscan’s lists of the bestselling books for 2013 were published at the end of last week, the trade’s comprehensive account of print book sales across what the company estimates is at least 80 percent of the print market. (There is still no public tracking service for ebook sales.) But direct comparisons about changes in print sales for the year are hard, because Bookscan expanded its data pool for 2013 by adding Wal-Mart sales. So total sales tracked expanded as Wal-Mart added between 5 and 10 percent to the total data pool. For year-over-year comparisons, there is the Bookscan’s subsection […]