Here's How Taylor Swift Has a Songwriting Credit on Olivia Rodrigo's 'Sour' Album

Olivia Rodrigo claims to be the "biggest Swiftie in the whole world," and now she has a Taylor Swift credit on her debut album to prove it.

Sour, which arrives at midnight ET, includes the song "1 Step Forward, 3 Steps Back," which -- Billboard can confirm -- interpolates Swift's "New Year's Day" from her 2017 album Reputation. Swift and her frequent collaborator Jack Antonoff each have writing credits on the song, whose title cleverly nods to Swift's numerology with "1" and "3" forming the pop superstar's lucky number 13. Additionally, all the numbers of Sour's release date on Friday (May 21) add up to 13: 0 + 5 + 2 + 1 + 2 + 0 + 2 + 1 = 13.

Although the new song is not a proper collaboration between the two, the 18-year-old breakout artist did meet her heroine for the first time at the 2021 Brit Awards on May 11, where Rodrigo performed her Billboard Hot 100 No. 1 hit "Drivers License" and Swift received the Global Icon Award.