In ice dancing, couples are required to perform choreographed dance routines on ice. It differs from pair skating in that it does not allow movements of strength, such as jumps or overhead lifts. Ice dance routines are similar to ballroom dances, and, typically, partners are not supposed to separate by more than two arm-lengths. The sport gained popularity in the 1930s, and the first world championships were held in 1950. When did ice dancing become an Olympic event? Discuss