By Dawn C. Chmielewski, Los Angeles Times

Book sales rose 6.2 percent last year in the U.S., thanks to the continued growth of electronic publishing, according to newly released StatShot data from the Association of American Publishers.

Electronic books, which a decade ago represented a tiny fraction of the industry’s revenue, now are the fastest-growing segment of the publishing business. Indeed, sales of digital versions of books for children and young adults more than doubled in 2012 from a year earlier.

The digital transition has been gathering momentum since the 2007 introduction of e-readers such as Amazon’s Kindle, and accelerated with the soaring popularity of tablet computers that followed the 2010 launch of Apple’s iPad.

E-books account for an increasing share of the industry’s sales, rising from 1 percent of revenue in 2008 to nearly 23 percent of sales in 2012, according to data provided by nearly 1,200 publishers.

Total trade book sales in the U.S. reached $7.1 billion in 2012, up from $6.7 billion the prior year.

Sales of adult fiction and nonfiction reached nearly $4.9 billion last year, up 5.6 percent from 2011. Digital sales in those categories rose 33 percent to nearly $1.3 billion, with the digital revenue gains more than making up for declines in hardcover book sales, which fell 6.7 percent to $1.4 billion. Paperback book sales rose 6.2 percent to $1.5 billion.

Children’s and young adult book sales rose 13 percent to nearly $1.7 billion in 2012, compared with the prior year. Revenue from children’s and young adult e-books jumped 121 percent to $233 million. Hardcover books still dominate the category, accounting for nearly $830 million in sales.

Sales in the religion category fell 5.4 percent to $576.6 million in 2012. Digital book sales in the category rose 20 percent to $57 million in 2012, while publishers reported declines in paperback and hardcover revenue.