On August 25th IU's entertainment label, Loen Entertainment thanked their fans via twitter and wrote,

"The Fans have put up an ad congratulating IU's upcoming 3rd year (September 18th) anniversary. Everyone passing by keeps looking at the ad, the fan's are so smart. Let's go on for another 100 years! Thank you!"

In the ad, fans have animated IU showing the progression of her career with an arrow, listing her�debut song to her most recent titles. Congratulations to IU for her upcoming 3rd year anniversary. Source: seountn via Nate