Year in Music 2017

'United State of Pop' Premiere: Watch DJ Earworm's Mash-Up of 2015's Biggest Hits (Exclusive)

Each year since 2007, DJ Earworm (real name Jordan Roseman) has taken the biggest tunes of the year and combined them into one ultra-catchy, viral-ready mash-up called "The United State of Pop." This year, the challenge got even more involved: Instead of the top 25 tunes like in years' past, Roseman would do a mash-up with 50 of the tunes that defined 2015.

The result is "50 Shades of Pop," a five-minute jam that highlights everything from Justin Bieber to Drake. It's no surprise that Taylor Swift, who ruled the charts all year with various tracks off 1989, sees many of her tunes as part of the megamix. 

"I try to get a feel of what is in the zeitgeist," he says about his process, which finds him using the Billboard charts for song selection. "Music has been going through a softer phase than it was a few years ago so there's that return of adult contemporary. That's maybe represented by the Ellie Goulding track, it's very lush and soft. And then there's sort of retro, uptempo dance stuff, and that's represented by The Weeknd track."

"It's a more eclectic mix than it was five years ago," he explains about the diversity of tunes that blew up the charts this year.  

As for late-in-the-year showstopper Adele, of course she made the cut. "It wouldn't be a year in summary without her."

Check out 2015's mix exclusively below. 

Update: Once "50 Shades of Pop" debuted earlier today, it hit No. 4 on the on the real-time Billboard + Twitter Trending 140 chart.