Audible, a subsidiary of Amazon, highlights its original downloadable audiobooks. (Audible Images)

If your idea of a good time reading is to do it with your ears, you’re in good company. Digital audiobooks are outpacing even ebooks in sustained growth.

Long gone are the days when listening to Stephen Hawking’s A Brief History of Time on a commute meant carefully swapping out nearly a half-dozen cassette tapes, back when “audiobook” was synonymous with “books on tape.”

Three decades later, the almost six-hour introduction to the Big Bang and black holes is a quick download purchase from Audible, or freely borrowed from a public library. Even if there’s no consistent agreement about whether these should be called digital audiobooks, e-audiobooks, downloadable audiobooks or, in the case of one major player, Audible books.

The e-audiobook category is so popular that the Association of American Publishers (AAP) cited it as “the fastest growing format” in its 2018 StatShot Annual Report released last month. The trade group’s U.S. book publishing statistics for industry net revenue cover everything from fiction and non-fiction to textbooks and professional books, in all formats.

Downloaded audio, the AAP reported, showed 28.8 percent year-over-year growth from 2016 to 2017, and 146.2 percent growth over the five years from 2013 to 2017. AAP added that in online retail channels, 10.5 percent of publisher sales are now from downloaded audio, 27 percent from ebooks, and the rest from print or other formats.

While downloaded audio’s online retail share may be less than ebooks’ current percentage, ebooks have hit a rough spot in growth over the past couple of years. Declines in both traditional publisher ebook unit and dollar sales were reported in 2017 (while indie author sales seem healthy). E-audiobooks, though, appear to be going nowhere but up.

But it does have catching up to do with other formats in terms of absolute dollars. “Despite the dramatic growth in downloaded audio,” AAP’s Marisa Bluestone said, “it still represented only 5.1 percent of trade publisher revenue in 2017.” That’s $820 million out of not quite $16 billion, if you’re doing the math.

Seattle Public Library digital audiobook circulation. (SPL Image)

However, it’s not just e-audiobook sales that are showing growth. So is digital audiobook library borrowing. Overdrive, which provides a digital ebook and audiobook distribution system for libraries, made a point of noting that earlier this year.

Seattle Public Library was one of Overdrive’s top five libraries for digital checkouts in 2017. SPL’s digital audiobook circulation as of the end of July 2018 was at nearly 541,000, after hitting a new peak of just over 730,000 for all of 2017. That reflects consistent growth each year going back to 2013.

Overall, digital audiobook use, whether that audio is bought or borrowed, appears to be hitting new heights. Pew Research Center earlier this year seemed to offer confirmation when it reported “a modest but statistically significant increase” in audiobook listening, rising from 14 percent of U.S. adults in 2016 to 18 percent in 2018. At the same time, Pew noted ebook reading was slightly down over the same time period.

This hasn’t gone unnoticed by ebook sellers and producers. “Audible has been experiencing double-digit growth year-over-year for many years,” said Beth Anderson, EVP and publisher of Audible, founded in 1995 and a subsidiary of Amazon for the past decade. “People are busy and enjoy being able to fit books and other content into their lives while they are doing something else.”

So who, and what, is all this growth coming from?

Pew’s research showed the sharpest uptake among two demographic groups, younger adults and college graduates. Use by each increased seven percentage points over two years. Overall, nearly one-quarter of 18-to-29 year olds have listened to an audiobook in the past 12 months, up from 16 percent in 2016.

Ebooks plateau, while audiobooks increase in use. (Pew Image)

Pew doesn’t comment beyond its published survey results. But others say what’s popular in digital audio seems to be fiction. Even better if it’s read aloud by a well-known name.

“Fiction audiobooks are more popular than non-fiction for both adult and children’s/young adult adult books,” AAP’s Bluestone told GeekWire, even though adult non-fiction brings in the most trade publisher revenue from all formats.

Audible’s Anderson appears to agree. “Audible listeners have very broad tastes, but mysteries and sci-fi seem to be perennial favorites,” Anderson said. “Literary fiction and business information are also very popular.” The Seattle Public Library says 58 percent of all of its downloadable audiobook circulation is adult fiction.

And if that voice coming through a smart speaker or earbuds is a familiar one, it helps. “Books read by a celebrity are very popular, regardless of category or genre,” said Frank Brasile, selection librarian for Seattle Public Library. “Whether it’s a celebrity or entertainer reading their memoir, or another well-known personality narrating a work of fiction or nonfiction, these titles do exceptionally well.”

More than 22,000 digital audiobooks are available from Seattle Public Library through Overdrive.

Brasile said the top title at Seattle Public Library over the past twelve months is The Girl With the Lower Back Tattoo by Amy Schumer. Also popular: Carlo Rovelli’s The Order of Time, a science book about the nature of time. While that second title may seem an odd front-runner, the audiobook is narrated by Benedict Cumberbatch. Brasile said The Order of Time audiobook is more popular than the ebook, and is almost as popular as the print book.

Perhaps also fueling this popularity are new, original digital audiobooks being produced that didn’t exist first in print or as ebooks.

Audible, which calls itself the largest seller and producer of downloadable audiobooks and other spoken-word entertainment, recently released an Audible Original by Vanity Fair contributor Michael Lewis. Rather than writing one of his 10,000-word magazine articles, Lewis created a piece for Audible and narrates it himself. The Coming Storm is said to be the first of four new Lewis audio original stories for Audible.

“The audio medium enhances the digestibility and accessibility of his signature nonfiction,” Anderson said of Lewis’ latest work. She noted Audible’s production of original content has a long history and wide range, from theater productions to celebrity stories such as David Spade’s recent memoir.

Yet even while it increases the total number of available digital audio titles, original work can be a double-edged sword. Content and licensing issues may restrict availability for libraries, many of which depend on the Overdrive distribution system.

“One of the challenges is that our audiobook collection is limited, because Audible has exclusive content that is only available from Amazon,” said SPL’s Brasile. “Our offerings are more limited than in other formats,” like ebooks.

However, there’s pretty unanimous agreement that changes in titles, technology and the very human factor of time are contributing to digital audiobooks’ uptake.

Audible’s Anderson points to the “ubiquity of smartphones and smart speakers,” the Audible app, and that audio is convenient. She also cites a recent University College London study it commissioned that found Audible books are more emotionally engaging than watching television or movies.

While not able to say what the main driver is for increasing popularity, AAP’s Bluestone said, “some reasons may include ongoing investments from publishers, increased selection of books, more celebrity narrators, developments in technology that make listening more convenient, and newer models for consuming the books.”

And perhaps one driver in crowded cities is traffic. “In urban Seattle there are lots of public transit commuters who could be fueling the growth,” said Rachel Martin, SPL’s assistant manager of collection services. Martin also called out technology improvements for borrowing audio, such as Overdrive’s Libby app, which “has simplified the number of steps patrons take before they are listening to a book.”

So from one standpoint, e-audiobooks represent a standalone success story for digital content.

But from a larger perspective, it’s the continuation of a longer-term digital conversion. We became conditioned as radio moved from terrestrial broadcasts to audio streams, audio became chunked into podcast files, and then downloadable files extended to narrated book length.

Call it a trained human ear, evolved by technology.

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