According to Publisher’s Weekly, a report by the Association of American Publishers’ shows that overall publishing industry sales fell by 2.6% last year when compared to figures from 2014. Now that we have a clearer picture of the industry’s struggles in 2015, we can tell that sales declined in five of the seven major markets. The only industry segments to show improvement, in fact, were adult books and books from religious presses, which increased sales by 2.2% and 1.2% respectively. Overall industry revenue fell from $15.82 billion in 2014 to $15.41 billion in 2015.

One of the more glaring narratives to come from the report shows that digital audiobook sales, which rose by nearly 40%, helped carry the adult books segment out of the red. It’s remarkable, too, that audiobooks should be booming in a historical moment that privileges debate about the print vs. digital divide. Along these lines, too, adult coloring books, which are print but not conventionally so, helped bolster trade paperback sales, which rose by more than 16%. And, as was projected, ebook sales fell by 9.5% in the adult category alone. In the YA category, PW reports, ebook sales declined by 43.3%.

The picture given by the AAP report, which surveys more than 1,200 publishers, confirms speculation about weak sales in broader publishing from the end of last year. But some have wondered whether a growing shadow market of self-published ebooks on platforms like Amazon’s KDP may be skewing the total numbers. Given that many of these ebooks aren’t registered by conventional means, it remains impossible to tabulate their impact on the market. The question of whether such a shadow market would bring overall industry numbers out of the red remains unanswerable.

Still, if we don’t have a clear idea of the impact of unregistered, self-published ebooks, perhaps we can look at the industry from the other direction. According to Publishing Perspectives coverage of a recent BEA talk given by Kempton Mooney, Nielsen Book Senior Director of Research and Analytics, the market share of Big Five publishers has declined yearly since 2012, when it controlled 46% of the market. In 2015, Big Publishing’s share had fallen by 12% to 34%. Meanwhile, the share of self-published books has risen by 7%, from 5% to 12%. And, for the first time, the combined share of self-published books and books by “very small publishers” (42%) is now larger than the total market share of Big Publishing (34%).

Meanwhile, quarterly numbers are coming in from several industry giants. With few blockbuster titles and declining ebook sales, Publisher’s Weekly reports, Hachette Book Group saw a 10.3% decline in sales (though it maintains that it was a profitable quarter). Despite falling sales, Michael Pietsch, Hachette’s CEO, points to sales of Hamilton: The Revolution and the further incorporation of Perseus Book Group as signs of a rebound later this year.

HarperCollins posted a similar decline in revenue, which it attributed to falling ebook sales and difficulties with foreign currency, as well as the absence of blockbusters on the level of the Divergent series. It did manage to post higher print numbers, however, due to the runaway success of Harper Lee’s Go Set a Watchman.

For Simon & Schuster’s part, revenue compared to this period in 2015 was flat, although it did experience an 8% increase in earnings. Reflecting 2015 trends, adult sales were down slightly, while digital audio downloads continued to increase, which almost kept overall digital sales, made sluggish by ebook revenue, out of the red.

Penguin Random House emerged as the one bright spot in Big Publishing’s most recent quarter by posting an 11.8% rise in revenue. Sales were led by a number of blockbuster books, including works by Paula Hawkins, Marie Kondo, E.L. James, Ta-Nehisi Coates, and Dr. Seuss.

With its year-by-year decrease in market share, and its dismal 2016 quarterly sales numbers (Penguin Random House excepted), Big Publishing’s ongoing shrinkage appears inevitable, although several questions remain. Will declining ebook sales stabilize, as some suggest? Or will Amazon, which posted a 28% increase in sales at the end of April, partly on the strength of Kindle Fire sales, continue to eat into the ebook market (presuming that is what is now happening)?

On the other hand, it must be admitted that a category uniting self-publishers with small publishers is little more than a heuristic. In broader publishing, Big Publishing still forms the only counterweight to Amazon, and the galaxy of small and smaller publishers flourishes (as ever)in spite of both.