Neither Justin Bieber nor Rihanna released an album (or even a solo single) in 2017, but both continued to lord over the pop world -- and manage to stay on the charts. Below, a timeline of how each star stayed hyper-relevant to the music world over the past year, including every chart triumph, super-collab and surprise feature.

Feb. 24: Future’s second album of 2017, HNDRXX features Rihanna on “Selfish,” the full-length’s first single.

March 25: Rihanna’s “Love on the Brain,” off 2016’s ANTI, peaks at No. 5 on the Billboard Hot 100 more than six months after its debut.

April 14: Kendrick Lamar drops DAMN. with Rihanna offering verses on “Loyalty,” which hits No. 2 on R&B/Hip-Hop Airplay.

April 17: Bieber jumps on a bilingual remix of Luis Fonsi and Daddy Yankee’s “Despacito” that tops the Hot 100 for 16 weeks.

April 28: Bieber guests on DJ Khaled’s Hot 100 chart-topper “I’m the One,” alongside Quavo, Chance the Rapper and Lil Wayne.

June 16: Khaled’s follow-up, “Wild Thoughts,” features Rihanna with Bryson Tiller. The song goes on to hit No. 2 on the Hot 100.

June 29: Bieber’s third feature of 2017 comes courtesy of EDM star David Guetta’s “2U.” It debuts at No. 16 on the Hot 100.

Aug. 17: The first co-lead of Bieber’s 2017 is with producer BloodPop for “Friends,” which bows at No. 5 on Digital Song Sales.

Nov. 1: Rihanna raps! Her N.E.R.D collaboration “Lemon” becomes the trio’s first Hot 100 hit, bowing at No. 63.

This article originally appeared in the Dec. 30 issue of Billboard.