Bowker, the ISBN provider, found that the number of self-published books in 2012 rose 59% to over 390,000 titles. Ebooks have led the charge, although print books still accounted for about 60% of self-published titles.

The analysis also found that more than 80% of self-published titles came from just eight companies, including Smashwords and CreateSpace. Fiction is the most popular self-published genre followed by inspirational/spiritual works, books for children, and biographies.