The number of traditionally published print books rose 6% in 2011, to 347,178, according to preliminary figures released Tuesday morning by Bowker. For the first time, this year, Bowker combined self-published titles with books from mainstream houses in the traditional column and the increase in output was led by self-published books, Bowker said. The number of print books published by traditional houses was about flat in the year. (The number of all self-published titles released by Bowker at the uPublishU conference on Sunday was 211,269, which includes print and e-books.)

Total book output from traditional and nontraditional companies fell 63% in 2011, to 1,532,623, due to the steep decline in books from reprint/POD houses that specialize in public domain titles sold mainly on the Web. The number of nontraditional titles fell 69%, to 1,185,445. The growth in that field had been unsustainable, noted Kelly Gallagher, v-p, Bowker Market Research; even with the decline in 2011, the output from nontraditional companies rose 3,532% between 2002 and 2011.

Among the traditional publishing categories, output growth was strongest in education, up 20%, while the number of fiction titles rose by 13%. The number of religion books produced increased by 12%, and the production of juvenile books as well as biographies and business books increased by 11% each. Losing ground last year were technology titles, where output fell by 11%, and science, with production down 13%. Production of history titles declined 7% and general works output fell 1%.