http://www.theguardian.com/books/2015/apr/11/traditional-books-new-chapter-success-london-book-fair Total spending on print and electronic books increased by 4% to £2.2bn in 2014, according to market data firm Nielsen. Ebooks now account for around 30% of all books published, including almost 50% of adult fiction. But the decline in print is levelling off as migration to ebooks declines. For some in the industry, it is a sign the dust is beginning to settle after the great digital shake-up.
Thats great to see, but in all honestly i never really felt that people had given up on reading in the same way the media liked to report. People love stories, now more than ever. We just have more options for consuming them. People read fanfic in message boards. They follow reddit posts where users are posting about a crazy event in their lives. If you come up with a great and engaging piece of writing, people will consume it...your options for how to deliver that writing have simply increased immensely with the introduction of digital media.
The big question is: where are they getting these numbers from? They can presumably get sales numbers from big publishers, but I don't believe Amazon and other retailers release any numbers for books self-published through them.
looking at her history I would say she has access to a lot of financial data. http://www.theguardian.com/profile/jennifer-rankin