It's been a long time coming, Argentina. Taylor Swift hit the stage this week after a 10-week hiatus in the Eras Tour.

"I'm having the time of my little life up here," she said before revealing her first surprise song to a sold-out Buenos Aires crowd. "On the Eras Tour, a tradition that we sort of started is that I try to play two different songs in the acoustic section that I've never played live before. So I'm going to keep that tradition going tonight. I have two songs that I've never attempted to play live before."

On Thursday night, she performed "The Very First Night (Taylor's Version) [From the Vault]" from "Red (Taylor's Version)" on her guitar and "Labyrinth" from "Midnights" on the piano during the acoustic surprise song set.

The set comes some 37 songs into Swift's massive 45 song set list, and the songs vary from show to show.

Kayla Wong, the "Data Swiftie", posted a list of songs Swift still has left as surprise songs.

"If Taylor goes by the cadence of she can't repeat songs unless it's off of 'Midnights' or something that she messed up and from that," Wong said, "there's 80 songs."

Wong, 28, has an Excel file of song titles, song lyrics, lengths of songs and all minutiae surrounding Swift. She creates graphics around her statistic findings and posts them to her instagram account @headfirstfearless.

Taylor Swift's remaining surprise songs:What you still might hear on the Eras Tour

Here is a list of all of Taylor's secret songs prior to Argentina:

• Glendale, Arizona (March 17) - "mirrorball" and "Tim McGraw"
• Glendale, Arizona (March 18) - "State of Grace" and "this is me trying"
• Las Vegas (March 24) - "Our Song" and "Snow on the Beach"
• Las Vegas (March 25) - "cowboy like me" (with Marcus Mumford) and "White Horse"
• Arlington, Texas (March 31) - "Sad Beautiful Tragic" and "Ours"
• Arlington, Texas (April 1) - "Death By a Thousand Cuts" and "Clean"
• Arlington, Texas (April 2) - "Jump Then Fall" and "The Lucky One"
• Tampa, Florida (April 13) - "Speak Now" and "Treacherous"
• Tampa, Florida (April 14) - "The Great War" (with Aaron Dessner) and "You're On Your Own Kid"
• Tampa, Florida (April 15) - "mad woman" (with Aaron Dessner) and "Mean"
• Houston (April 21) – "Wonderland" and "You're Not Sorry"
• Houston (April 22) – "A Place In This World" and "Today Was A Fairytale"
• Houston (April 23) – "Begin Again" and "Cold as You"
• Atlanta (April 28) – "The Other Side of the Door" and "Coney Island"
• Atlanta (April 29) – "High Infidelity" and "Gorgeous"
• Atlanta (April 30) – "I Bet You Think About Me" and "How You Get The Girl"
• Nashville, Tennessee (May 5) – "Sparks Fly" and "Teardrops On My Guitar"
• Nashville, Tennessee (May 6) – "Out of the Woods" and "Fifteen"
• Nashville, Tennessee (May 7) – "Would've Could've Should've" (with Aaron Dessner) and "Mine"
• Philadelphia (May 12) - "gold rush" and "Come Back... Be Here"
• Philadelphia (May 13) - "Forever & Always" and "This Love"
• Philadelphia (May 14) - "Hey Stephen" and "The Best Day"
• Foxborough, Massachusetts (May 19) - "Should've Said No" and "Better Man"
• Foxborough, Massachusetts (May 20) - "Question...?" and "Invisible"
• Foxborough, Massachusetts (May 21) - "I Think He Knows" and "Red"
• East Rutherford, New Jersey (May 26) - "Getaway Car" (with Jack Antonoff) and "Maroon"
• East Rutherford, New Jersey (May 27) - "Holy Ground" and "False God"
• East Rutherford, New Jersey (May 28) - "Welcome To New York" and "Clean"
• Chicago (June 2) – "I Wish You Would" and "the lakes"
• Chicago (June 3) – "You All Over Me" (with Maren Morris) and "I Don't Wanna Live Forever"
• Chicago (June 4) – "Hits Different" and "The Moment I Knew"
• Detroit (June 9) – "Haunted" and "I Almost Do"
• Detroit (June 10) – "All You Had To Do Was Stay" and "Breathe"
• Pittsburgh (June 16) – "Mr. Perfectly Fine" and "The Last Time"
• Pittsburgh (June 17) – "seven" (with Aaron Dessner) and "The Story of Us"
• Minneapolis (June 23) – "Paper Rings" and "If This Was A Movie"
• Minneapolis (June 24) – "Dear John" and "Daylight"
• Cincinnati (June 30) – "I'm Only Me When I'm With You" and "evermore"
• Cincinnati (July 1) – "ivy" (with Aaron Dessner), "I miss you, I’m sorry" (with Gracie Abrams) and "Call It What You Want"
• Kansas City, Missouri (July 7) – "Never Grow Up" and "When Emma Falls in Love"
• Kansas City, Missouri (July 8) – "Last Kiss" and "dorothea"
• Denver (July 14) - "Picture To Burn" and "Timeless"
• Denver (July 15) - "Starlight" and "Back To December"
• Seattle (July 22) - "This Is Why We Can't Have Nice Things" and "Everything Has Changed"
• Seattle (July 23) - "Message In A Bottle" and "Tied Together With A Smile"
• Santa Clara, California (July 28) - 'right where you left me' (with Aaron Dessner) and 'Castles Crumbling'
• Santa Clara, California (July 29) - 'Stay Stay Stay' and 'All of the Girls You've Loved Before'
• Los Angeles (Aug. 3) – "I Can See You" and "Maroon"
• Los Angeles (Aug. 4) – "Our Song" and "You Are In Love"
• Los Angeles (Aug. 5) – "Death By A Thousand Cuts" and "You're On Your Own, Kid"
• Los Angeles (Aug. 7) – "Dress" and "exile"
• Los Angeles (Aug. 8) – "I Know Places" and "King of My Heart"
• Los Angeles (Aug. 9) – "New Romantics" and "New Year's Day"
• Mexico City (Aug. 24) - "I Forgot That You Existed" and "Sweet Nothing"
• Mexico City (Aug. 25) - "Tell Me Why" and "Snow on the Beach"
• Mexico City (Aug. 26) - "Cornelia Street" and "You're On Your Own, Kid"
• Mexico City (Aug. 27) - "Afterglow" and "Maroon"

Taylor Swift set list:Here are all the songs on her epic Eras tour

Follow Bryan West, the USA TODAY Network's Taylor Swift reporter, on Instagram, TikTok and X as @BryanWestTV.