Fiction is the leading sales driver of e-books, and just how dominant that segment has been is clearly seen in a new market study just released by Bowker. According to "2010–2011 U.S. Book Consumer Demographics & Buying Behaviors Annual Review," fiction accounted for 61% of unit sales in 2010 and 51% of revenue, putting it far ahead of other segments. The children's segment generated 12% of unit sales in 2010, placing it second behind fiction, while nonfiction accounted for the second highest amount of e-book revenue in 2010, with the segment representing 14% of sales.

Another indication of e-books' importance in the fiction market is the format's share of unit sales among genres. Of the 10 genres where e-books represented a significant portion of sales in 2010, only one, biography/autobiography, was nonfiction. The genre where e-books accounted for the highest portion of unit sales was literary/classics, where e-books generated 20% of unit sales last year. The high percentage reflects the large number of public domain titles of classic books being sold through a variety of Web sites.

The Bowker study, written in cooperation with PW, documents the influence e-books are having on every aspect of the book business, even though the format's market share of all book-buying was only 4% of units at the end of 2010. One major impact is on sales of all books by channel. Boosted by sales of e-books and led by Amazon, online retailers accounted for more sales than bookstore chains in 2010, capturing 30% of sales compared to 29% for the major chains. In 2009, online retailers accounted for 19% of sales, while the chains had 37%. Not only are online retailers benefiting from higher e-book sales but consumers who buy e-books from a particular site often buy their print books there as well. It is that combination of e-book and print book sales that had Amazon and Barnes & Noble tied as the country's largest booksellers last year.

More information about the study, which is derived from Bowker's PubTrack Consumer service, which gathers data from 40,000 book-buying men, women, and teens, is available by e-mailing