E-Reading increases and physical books decline

With prices that vary considerably (E-Books may be as much as 30-50% cheaper online or more) and with options such as the Nook or Kindle apps for PCs, it is no wonder that electronic reading has jumped and traditional books have declined. Then, if you add in how dedicated E-Readers have gotten cheaper and  tablet and smartphone ownership has spiked, more and more readers have the option of having a decent, cheaper reading experience than traditional books.

This does not mean that E-Books are better than traditional hard copy books, it just means that the value and price equation has convinced many readers to favor e-books over hard copy, physical books.

http://libraries.pewinternet.org/2012/12/27/e-book-reading-jumps-print-book-reading-declines/