According to Official Guinness Records,
The all-female theatre-based "idol" collective AKB48 (Japan, 2005-present) consisted of 88 members as of March 2013. The all-singing, all-dancing group, which can boast career sales in excess of 22 million singles and albums, is divided into four teams: Team A, Team K, Team B and "kenkyūsei" ("trainees"). Membership is based on auditions and the girls – aged between 13 and the mid-20s – “graduate” when they get older, to be replaced by new members.
For a complete list of 2013 records, please visit 2013 Guinness Records in Japan.