One in five publishers is now generating more than 10% of their revenues from e-books, with Amazon slowly decreasing in importance.
The numbers are revealed in Aptara's third annual e-book survey of publishers, representing more than 1,300 book publishers from the trade, education, professional and corporate markets.
The vast majority of book publishers (85%), across all market segments, are producing print and e-book versions of their titles. The percentage of trade publishers producing e-books has risen from 50% to 76% in two years.
Amazon.com was listed as the biggest generator of sales by 56% of trade publishers, and by 38% of all publishers, with their own websites the second biggest category. Apple, Barnes & Noble and Kobo all ranked much lower, with just 2% plumping for Apple's iBookstore and 1% for the Nook and Kobo.
The main drivers for producing e-books across all publishing market segments are "increasing revenue" (42%) and "increased customer demand" (36%). However, two out of three e-book publishers have still not converted the majority of their backlist titles to e-books.
The overwhelming percentage of responding publishers across all market segments were from English-speaking countries including United States (70%), United Kingdom (8%), Canada (3%), and Australia (3%).
Meanwhile the number of Americans using an e-book reader has almost doubled during the last 12 months, according to another survey. The Harris Poll also revealed one in six Americans who do not have an e-reader intend to buy one during the next six months. This may be welcomed by publishers as e-reader owners are reading more books, according to the survey.
Overall, 16% of Americans read between 11 and 20 books per year with 20% reading more than 21. However, a third of those who own a Kindle, Nook or other device read 11-20 books a year with 27% reading more than 21. E-reader owners are also more likely to buy books, with 17% purchasing between 11 and 20 and 17% buying more than 21 over 12 months.
The top genres among e-book owners are crime and thriller (47%), science fiction (25%), literature (23%) and romance (23%). In non-fiction, biography is most popular (29%), then history (27%) and religion and spirituality (24%).
Harris surveyed 2,183 people during a week in July 2011. It found 8% of adults used an e-book reader 12 months ago, compared to 15% now.