Industry sales were just about flat in 2013, falling by less than 1%, to $27.01 billion, from $27.12 billion in 2012, according to the newest figures from BookStats, the industry statistics program from the AAP and BISG.

Sales in the trade segment, the industry’s largest, fell 2.3%, to $14.63 billion, but revenue rose in the three other major categories. Sales of professional and scholarly books increased 1.3%, to $3.62 billion, while sales in the higher education category rose 1.1%, to $4.34 billion. Sales in the pre-k-12 segment increased 3.4%, to $4.41 billion.

Within the trade group, which BookStats includes religion in, only adult nonfiction posted a sales gain in the year, with revenue up 5.4%, to $4.65 billion. Sales of adult fiction fell 7.1%, to $5.04 billion, in part because of the fall-off in sales of the Fifty Shades trilogy, which had such huge success in 2012. Juvenile fiction sales dropped 4.9%, to $2.19 billion; the fall-off in sales of the Hunger Games trilogy, which was huge in 2012, had an impact here. Juvenile nonfiction sales fell 5.8%, to $644.8 billion. And sales in the religion segment fell 1.1%, to $1.37 billion.

In terms of formats within trade, e-book sales fell to $3.03 billion from $3.06 billion in 2012, due to a large decline in sales of e-books in the juvenile fiction segment, where sales declined 25.5%, to $347.7 million. In adult fiction, e-book sales rose in the year to $1.92 billion, a 2% increase over 2012. E-books accounted for 38% of adult fiction sales in 2013, compared to 34.7% in 2012. In adult nonfiction, e-book sales rose 6.8%, to $593.1 million, accounting for 12.8% of nonfiction sales, up from 12.6% in 2012. In the religion category, e-book sales rose 14.4%, to $146.2 million. While e-book sales for trade fell in 2013, the number of units rose 10%, to 512.7 million.

Within trade, hardcover remained the largest format in 2013, with revenue of over $5.14 billion, followed by trade paperback, with sales of $4.76 billion. Sales of mass market paperback, while falling 6.7%, still generated revenue of $781 million in the year.

Totals for BookStats are based on reports from 1,616 publishers which are then extrapolated to account for non-reporting companies.