As sales in the traditional trade segments plunged in September, e-book sales jumped 158.1%, according to the monthly sales estimates released by the Association of American Publishers. Sales for the 14 publishers that reported e-book sales hit $39.9 million in the month, and were up 188.4% in the first nine months of the year to $304.6 million. In contrast, sales in the three adult trade segments, adult hardcover, trade paperback and mass market paperback, all fell by more than double digits with the adult hardcover segment experiencing the biggest decline with sales down 40.4% at the 17 publisher who reported sales to the AAP of $180.3 million. The only other segment to post a significant sales gain in September was downloadable audio with sales from the nine reporting companies up 73.7%, to $7.7 million. Sales of audio CDs fell 42.6%, to $11.6 million, in the month at the 22 reporting companies.