Each point is a rolling 30-day score ending on that date, sampled weekly. May differ from the window composite above.
f(x) were a South Korean girl group formed by SM Entertainment, debuting on September 1, 2009 with the digital single "La Cha Ta." Originally five members, the group consisted of Victoria, Amber, Luna, Krystal, and Sulli, who left in 2015 to focus on acting. The group's name plays on mathematical function notation, with "f" suggested as "flower" and "x" representing the female chromosome. f(x) were positioned with an experimental, electronic-leaning pop sound and an androgynous, trend-forward image that set them apart from their contemporaries. They released influential singles including "Nu ABO," "Electric Shock," "Rum Pum Pum Pum," and "4 Walls," and their album "Pink Tape" is frequently cited among the most acclaimed K-pop records of its era. Amber was noted as one of the genre's prominent tomboyish, rap-leaning members, while Luna and Krystal anchored the group's vocals, and Victoria led as the eldest member. As a second-generation act, f(x) became known for pushing the genre's sonic boundaries, and their work remains widely regarded as ahead of its time even after the group ceased regular activities, influencing later acts that embraced experimental, electronic-leaning pop.