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Way back in June, my cousin and I joined the pilgrimage of people who came of age in the mid-aughts trekking to New York City to see the musical adaptation of Mean Girls on Broadway. Though we were definitely going ironically, I believe that familiarity with the material is crucial to appreciating any theatrical performance, so on our drive up, I cranked the campy, sugared soundtrack on repeat until our ears were ringing. We listened to it again on the way back, and again the next day, and then I was immensely sick of it.

And then, last week, I and more than 83 million other Spotify users were treated to this year’s release of the music-streaming service’s annual Wrapped tool, which provides users with an animated slideshow breakdown of their individual listening history for the year. For example, mine told me that I listened to “non-mainstream music 90 percent more than the average Spotify user.” That is, my most played album of 2018 was the Mean Girls soundtrack, streamed for a total of four hours.

People love Spotify Wrapped. We love the stories that the thousands of hours of music we listened to this year tell about us. We love the embarrassing revelation of a guilty pleasure, or the reinforcement of a cultivated musical identity when the bands at the top of the list match the T-shirt collection in our drawers. If you use social media, you’ve almost certainly seen people you know posting screencapped portions of their Wrapped results alongside some highly enthused observation: Their top five artists “so perfectly encapsulated” them. Their data were thrown out of whack after they fell asleep one too many times listening to artists with names like White Noise for Baby Sleep. A friend texted me that “seeing top songs on Spotify Wrapped is like seeing an old best friend that you lost touch with.”

It’s apropos, then, that Spotify added an astrological component to this year’s Wrapped, telling some which astrological signs they listened to most this year. (A recurring combination was Ariana Grande and Selena Gomez, both Cancers.) The way Spotify touts the arrival of Wrapped results—“Find out everything there is to know about how you listened in 2018!”—is like stepping into a psychic’s parlor. We all want to know ourselves, and Spotify promises us an organized dredge of tea leaves, our true selves represented cleanly by the five songs we never even realized we listened to that much, each brightly colored slide a portrait of a complete and unique person—“because,” as the feature’s introduction reads, “no one else listened exactly like you.” Users read so much meaning into their results that Spotify’s Twitter support account has been inundated with angry replies from people convinced that their 2018 chart-toppers were incorrect or unfair.

Spotify Wrapped is a masterful coup of free advertising and an impressive display of consumer trust at a moment when our faith in tech companies is historically low. After all, to assemble your end-of-year hits playlist, the platform requires detailed information about everything you do and everything you hear when you use a platform many of us spend more time inside than any other. In 2016, the average Spotify user listened to roughly 2.5 hours of audio a day. That’s a colossal amount of data. In a year when other tech giants were taken to task by the government, the market, and the public for their privacy practices, it’s hard to imagine anyone would respond with such enthusiasm if Facebook, Twitter, or Google started sending out annual summaries of everything they’ve got on us.

That’s largely because Spotify feels different. Aside from some disputes over royalties that haven’t significantly hindered the company’s growth, Spotify is outwardly tame. The platform doesn’t have a comments section, and it got rid of messaging in 2017. Aside from a few second-order connectivity features—namely, the ability to stream and add to other users’ playlists and see what your friends are currently listening to—Spotify is a solitary experience, not a social network. Its personalized machine-curated playlists are a much-loved feature. And as personal as it is, music is less private than a chat history or cache of photos.

“The average music listener often uses music as a sort of aural wallpaper,” says Robert Prey, a media-studies professor at the University of Groningen, in the Netherlands. “It’s in the background and it’s not that important. It’s fun, and so people don’t take it as seriously.” In a November 2017 paper, the Swedish media scholar Patrick Vonderau coined the term Spotify effect to describe the way the platform has downplayed its market impact while emphasizing its clever design and fun, user-facing features. Spotify’s achievement, the paper concluded, was “the company’s ability to fold markets into each other: to make disappear an aggressive financial growth strategy and business set-up based on ad-tech engineering by creating an aura of Nordic cool and public benefit around its use of music.”

Spotify is cool and innocuous, and so is Spotify Wrapped. It’s a year-end package of low-stakes personal data, focused on you, for you—as Instagram-ready as the feature’s design is, only on the last of nine screens do you see an option to “share” the results on social media. Benjamin Johnson, an advertising professor at the University of Florida who researches how we selectively share our music tastes to influence self-presentation, says that Spotify has managed to avoid the “creepiness factor” by granting a maximum amount of user control over what people’s networks see of their listening history. As a result, Johnson says, a person reviewing Wrapped results “feels the control in that moment before they take the screenshot, where they can decide, Is this going to make me look good? or Does this reflect the story that I want to tell about myself?

Of course, just because it doesn’t feel that way doesn’t mean Spotify isn’t collecting a ton of valuable personal information. “We find that there’s incredible detail in the data,” Prey says. “There’s all this information: everything from what brand of headphones you’re listening to the music on, to if the volume was changed within songs, whether or not you resize the app’s windows.” In May, a Bank of England project found that it was possible to capture subtleties in peoples’ moods and preferences based on their Spotify listening patterns and other data.

For this reason, Prey is concerned that Spotify may become a prime example of what he calls “function creep.” Spotify’s data collection may remain stored away in the cloud, Prey wrote in a 2016 study, “or it may one day migrate out, as previously undetermined uses for correlating music taste with some other aspect of our lives are discovered. For example, data collected for the purpose of recommending music may be found to deliver a reliable predictor of financial solvency, IQ, or relationship status. What if a taste for early ’90s Nu Metal indicates a higher propensity to default on a debt repayment?” In other words, Spotify itself may have no real reason for tracking when you adjust the size of your app’s window, and you might not care that it does so—but should an opportunity to monetize that information arise, the company already has it. “As people say,” Prey quips, “data is the new oil.” (Spotify declined to comment on the record for this story.) Ultimately, the popularity of Wrapped may reveal more about our love for music—and occasionally, our inability to resist the charm of a catchy show tune—than it does about our protectiveness over our data.

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