The overall market shrank by 6% in that period, with much of the drop due to the children's/YA segment (religious and adult segments increased slightly). Both children's hardback and kid's ebook market segments are still normalizing after last year's anomalous spike in sales caused by the release of The Hunger Games movie.
The total book market dropped by 6.1% ($2 billion vs $2.13 billion), while the adult segment was up 1.3% ($1.39 billion vs $1.37 billion). The religious book segment also increased by 1.9% ($193.2 million vs $189.7 million), while the kids /YA segment dragged down the rest of the market.
Thanks to the fact that there's no blockbuster hit this year which matched last year's success of The Hunger Games, the kids book segment dropped by 26.8% ($417.5 million vs $570 million).
The overall ebook market remained flat for the first 4 months of this year, also largely due to a lack of a blockbuster hit. Nevertheless, adult ebooks and religious ebooks both posted modest gains in that period (12.4% and 7.9%, respectively). The only reason that the ebook market as a whole remained flat was that sales of kids ebooks dropped by 43.7%.
If you factor out the kids ebook market, then the other 2 segments average out to a 12.1% increase over last year. That's not great but it is also not the flattening out of ebook sales that Nicholas Carr would have you believe.
And if we focused on the adult market segment alone we'll see that the digital content (ebook & audiobook) made up 38.1% of the reported revenue in the first 4 months of 2013 vs 35% in the same period of 2012. That is not a flattening market, IMO.
Speaking of anomalous spikes in sales, the AAP is also saying that their figures are now showing the effect of the second publication of 50 Shades of Gray last April. I am not sure that claim is true for April, but sales of that book will likely be reflected in figures for May and June.
And while we are on the topic, let me share another reason that you shouldn't read too much into these figures.
50 Shades was immensely popular last year, with news reports from as early as February saying that it was a widely read best-seller. That title was even at the top of the Kindle Store best-seller list in March 2012 (and earlier).
Here's the fun part: Those early sales aren't reflected in AAP figures for the first 3 months of last year. At that time the book was still published by an Australian publisher who obviously was not an AAP member.
I bring this up to remind everyone that this data only reflects the sales of 1195 US publishers, and not the rest of the world (this includes indie pub and self-pub).
P.S. Here's the data, for those who are interested in playing along at home. Please note the absence of specific data for April; the AAP did not share that data so any stories which mention specific figures for April are at best iffy.