Drake was the “most streamed artist” of 2015, Spotify announced on Tuesday, registering 1.8 billion streams worldwide so far this year. The artist, whose album If You’re Reading This It’s Too Late, which also proved to be tops on the streaming service, attracted 46 million listeners. Rihanna took the top spot worldwide among female artists with over 1 billion streams and 57 million listeners, while Justin Bieber set a record on Nov. 13 by notching the most streams in a single day at 36 million.

The findings were released as part of Spotify’s annual Year in Music lists, which have historically provided insight into the interests of music lovers around the world. Indeed, with over 75 million listeners who streamed more than 20 billion hours of music, Spotify has become a desirable destination among music fans. With more than 20 million paying customers doling out $9.99 per month for ad-free listening, among other perks, Spotify has the most popular paid streaming service in the world. It’s just behind Pandora in total listeners, which has over 80 million. Apple Music, the service widely viewed as the chief competitor to Spotify, had approximately 6.5 million paid subscribers in Oct. The company also competes with Rdio, Deezer, and Jay-Z’s Tidal, among other streaming services.

Spotify’s 2015 recap provides a valuable look at listeners’ music tastes—Nicki Minaj was the most popular female artist in the U.S., topping Beyonce and Rihanna, and “Lean On” by Major Lazer was the year’s top song, for instance. However, the conspicuous absence of Taylor Swift and Adele, the year’s two top artists, may not tell the whole story of musical taste around the world.

Last year, Taylor Swift sent shockwaves through the music industry when she pulled her hit album 1989 from Spotify. The “Shake It Off” singer has publicly lambasted streaming services, saying that they are hurting the music industry in general and artists in particular.

“In my opinion, the value of an album is, and will continue to be, based on the amount of heart and soul an artist has bled into a body of work, and the financial value that artists (and their labels) place on their music when it goes out into the marketplace,” Swift wrote in an op-ed in The Wall Street Journal last year. “Piracy, file sharing and streaming have shrunk the numbers of paid album sales drastically, and every artist has handled this blow differently.”

Just hours before the launch of her smash-hit album 25, Adele announced last month that she would follow Swift’s lead and not offer her album on Spotify. While Adele has not commented on the omission, it was a major blow to Spotify. The British singer sold a record 3.4 million U.S. copies of the album in its first full week on store shelves, making it the biggest single-week sales tally for an album since Nielsen began tracking sales figures in 1991. As of this writing, her hit “Hello” has secured more than 554.8 million streams on music video streaming platform Vevo.

To put that into perspective, Drake’s “Hotline Bling,” one of his latest hits, has tallied just 145.3 million views on Vevo. “Lean On,” the most popular song on Spotify in 2015, has nearly 572,000 views on Vevo.

There are other ways to access streaming music and Vevo is not the only way to measure popularity. What is clear, however, is that Taylor Swift, who has been selling out huge venues with tens of thousands of people, and Adele, who has a once-in-a-lifetime hit on her hands, are leaving a massive void in Spotify.

Despite the criticism, Spotify has argued that it should be a destination for the latest and greatest music. The company has a Spotify Artists page outlining how it generates revenue through both ads and monthly subscription fees, and how it pays out royalties to artists. While it acknowledged that each time a person listens to a track, the “rights holders,” which can include artists and record labels, can make between $0.006 to $0.0084, it offered real-world scenarios. In those scenarios, it says that in July 2013 (the last time it provided figures) an artist offering a “global hit album” was making $425,000 per month. A Spotify Top 10 album generates $145,000 per month.

If Spotify reaches 40 million paid subscribers, the company says the global hit album category will generate $2.1 million per month in artist royalties.

“Even though we are currently generating millions of dollars in royalties for rights holders for the top artists each year, we’re just getting started and expect to earn artists and rights holders far more as we grow our user base,” the company says on its Artists page.

So far, however, those promises have done little to get the world’s two most popular artists to give in. And their absence from the service may have dramatically changed the makeup of this year’s Spotify roundup.

Spotify declined to comment on this report.

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