It accounts for nearly half of all book sales in the United States, including print and e-books, according to the Codex Group, which analyzes the industry. With the introduction of the Kindle in 2007, Amazon drove the e-book and self-publishing boom. It bought Audible, the audiobook producer and retailer, and Goodreads, the popular book review sharing site. It started a publishing company, and now has 14 imprints.

Last week, the company introduced Amazon Charts, weekly best-seller lists that track not only the top-selling digital and print books on Amazon, but the ones that customers spend the most time reading. Drawing on data collected from Kindle users and Audible listeners, the most-read list compiles which books are most popular with its customers across digital formats. It is data that Amazon has long collected but never made widely public.

“This is the first time we’re sharing this information with readers,” said Susan Stockman, who oversees Amazon Charts.

With its lists, Amazon aims to redefine the notion of a best seller, expanding it to include books that are “borrowed” from its e-book subscription service, and ones that are streamed on Audible. As a result, the lists give increased visibility to books that might not typically appear on other best-seller lists, like The New York Times’s or The Wall Street Journal’s. The inaugural Amazon Charts list for most-sold fiction features five books from Amazon Publishing, out of 20 on the list.

“This is their attempt to push back and say, we’re legitimate,” said Peter Hildick-Smith, the president of the Codex Group.

All of Amazon’s acquisitions and new features are having a cumulative effect, allowing the company to draw on its vast customer base and troves of data to discover what is popular, and return that information to customers, creating a lucrative feedback loop. Eventually, the weekly best-seller lists may be incorporated into displays in Amazon’s bookstores, and perhaps posted on Goodreads. They are already available on Alexa, Amazon’s virtual assistant, which will recite the new best-seller lists when asked.