Degree of difficulty

Degree of difficulty (DD, sometimes called tariff) is a concept used in several sports and other competitions to indicate the technical difficulty of a skill, performance, or course, often as a factor in scoring. Sports which incorporate a measure of degree of difficulty include bouldering, cross-country skiing, diving, equestrianism, freestyle skiing, gymnastics, rhythmic gymnastics, surfing, synchronized swimming and trampoline. Degree of difficulty is typically an objective measure, in sports whose scoring may also rely on subjective judgments of performance.

The International Federation of Gymnastics gives skills a difficulty rating of A, B, C, D, E, F, or G. Degree of difficulty is also enhanced by connecting skills together in combination.

The International Swimming Federation computes the degree of difficulty of dives according to a five-part formula, incorporating height, number of somersaults and twists, positioning, approach, and entry.

The International Federation of Gymnastics gives difficulty points for number of somersaults, number of body twists and the body position in somersaults (piked or straight). The total for a routine is the sum of the individual elements.

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