Their combined CD and DVD sales exceed 22 million copies in Japan alone. Their producer, Tsunku, is responsible for the composition of the majority of their songs and lyrics, production of their CD-sleeve covers, designing of their costumes and make-up and their live shows. The group is known for their ever-fluctuating line-up, with "graduations" and auditions held nearly every year. In recent years, the group has been making a concerted attempt to break into new markets in Asia, Europe and the US, performing at expos worldwide.