From The Association of American Publishers:
October 2018 marked the second time in two years that publishers saw modest revenue growth in eBooks (+4.4%), with increases for the format across all trade book categories. Aside from downloaded audio, eBooks had the largest percent of revenue growth for the month, compared to October 2017.
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Publishers’ revenues (sales to bookstores, wholesalers, direct to consumer, online retailers, etc.) were $1.16 billion in October 2018, down from $1.17 billion in 2017 (-0.8%). The trade book categories either remained flat or declined in October, while educational and scholarly publishing saw some revenue increases.
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October format preferences varied from 2018’s norms, with modest revenue growth for eBooks (+4.4%) and a decline in revenue for hardback books (-7.5%). eBook revenue increased in October for Adult Books (+3.0%), Childrens/YA Books (+17.3%), and Religious Presses (+12.0%).
However, for the year-to-date (Jan. – Oct.), eBook revenues were down -3.1% from the same period in 2017. Downloaded audio remains the format with the highest percent revenue growth year-to-date (+37.7%).
Link to the rest at The Association of American Publishers