Book sales rose 1.0% in 2008, to $40.3 billion, according to estimates released at a Friday afternoon panel by the Book Industry Study Group. Unit sales fell 1.5%. Within the trade segment, adult sales fell 2.3%, to $11.1 billion, while children’s sales declined 1.3%, to $3.6 billion. The religion segment had the worst performance in 2008, with sales down 10%, to $2.3 billion. Gains came in the professional, scholarly, elhi and college categories.

BISG used a new methodology this year, one that included surveys and interviews with small, medium and large publishers in an attempt to get a more “robust view” of the industry, BISG executive director Michael Healy explained. For several years before the new report, BISG did surveys to gauge the sales of independent publishers in addition to its traditional report, and the approach in the new study was aimed at integrating those sales into the main report, said Leigh Watson Healy, chief analyst at Outsell and head analyst for BISG Trends 2009. Watson Healy said responses from independent publishers to the 2008 survey, which was e-mailed to 70,283 publishers, were sufficient to give her confidence that “we have a statistically valid survey.” According to the report, approximately 32% of industry revenue, $12.7 billion, in 2008 was generated by more than 100,000 companies with sales below $50 million.

The new report also gives a breakdown of sales by format and channel. Investments that publishers have made in digital publishing, Watson Healy said, are beginning to pay off. Sales of digital books—excluding audiobook downloads—hit $113 million for adult trade publishers last year and $451 million for professional publishers. “It’s clear future growth will come from digital,” Watson Healy said. Trade e-book sales are expected to increase by just under 10% in 2009.

In looking at the current year, BISG Trends 2009 predicts that sales will rise 1.8%, to $41 billion, with units up 0.7%. Watson Healy sees a bit of a bounce back for the trade segments and slower growth for the professional and educational segments.

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