5 Years:
BTS - Spring day (Since 2017)
4 Years:
IU - Through the night (Since 2017, but #102 in 2021, else IU would have made it to 5 years as well)
Paul Kim - Meet You (Since 2018, so BTS wins by the year leading)
Paul Kim -Every day, Every Moment (Since 2018, so BTS wins by the year leading)
3 years:
BTS - Boy With Luv (Feat. Halsey)
AKMU How can I love the parting, I love you
IU- Blueming
Busker Busker - Cherry Blossom Ending
Jang Beom-jun I could feel the scent of your shampoo in the swaying flowers
Anne-Marie - 2002
Maktub - To you who shines today too (To You My Light) (Feat.
glow - Late at night in the alley in front of your house
Lauv - Paris In The Rain
2 Years:
BGs - BTS, BTOB, Winner. BTS has the most - 4 songs
GGs - Blackpink, Gfriend, Apink, Red Velvet, EXID, AOA, Twice, Mamamoo, OMG. BP & Twice have the most- 5 songs,
IU has 8 songs which have charted for 2 years. Most interesting is "Hold my hand", which tanked at #49 in 2011, came back to #12 in 2021, after a gap of 10 years
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Longevity apart,
IU has appeared 55 times in the top 100 of Gaon Year End Digital charts - features included.
BTS comes next with 31, so have a lot to catch up.