While Amazon yesterday reported lower-than-expected fourth-quarter earnings and a decrease in sales for physical books, the company also announced that sales for ebooks have been steadily climbing.

In a press release, Amazon CEO Jeff Bezos says, We’re now seeing the transition we’ve been expecting. After five years, ebooks is a multi-billion-dollar category for us and growing fast “ up approximately 70 per cent last year. In contrast, our physical book sales experienced the lowest December growth rate in our 17 years as a bookseller, up just 5 per cent.