The 6.0 system was divided into "technical merit", "required elements", and "presentation". The marks for each program ranged from 0.0 to 6.0, the latter being the highest. These marks were used to determine a preference ranking, or "ordinal", separately for each judge; the judges' preferences were then combined to determine placements for each skater in each program. The placements for the two programs were then combined, with the free skate placement weighted more heavily than the short program. The individual with the lowest sum of the factored placements was declared the winner. The 6.0 system was a ranking system. Skaters were ranked in comparison to each other in marks ranging from 0.0 to 6.0, with 6.0 being the highest possible mark. It was first introduced at ISU congress in 1901. Until that year skaters' marks ranged from 0 to 5. A 6.0 mark for technical merit was extremely rare. The 6.0 system went through various versions in terms of how scores were tabulated and compared with each other. Until 1980, for example, each judges' weighted scores from each phase of the competition were added together before computing ordinals, instead of using factored placements. Because compulsory figures were scored using a wider range of marks than the short program or free skating, this system allowed skaters to take a large lead in that segment of the competition, which made them effectively unreachable in later segments. The system of factored placements, in which ordinals were computed for each competition segment separately and factors applied to the relative placements rather than the raw marks, was proposed as early as 1971 by former Hungarian champion and World Referee Pál Jaross, and finally adopted for the 1980–1981 season. In 1998, the method by which placements within a segment were computed was changed from "best of majority"—ranking skaters by the highest ordinal for which they received a majority vote of the judges—to a system of "one-by-one" comparisons between the ordinals of all the skaters.
6.0 as a mark
While the 6.0 mark by itself did not mean anything out of context, it was often used as a sign of perfection. British ice dancers Jayne Torvill and Christopher Dean earned nine 6.0 scores for artisticimpression at the 1984 Winter Olympics, and remain the only ice skaters to ever achieve that score in the Olympics. Michelle Kwan of the United States holds the record for most 6.0s in international competition. The rationale for marking on a scale of 0 to 6.0, rather by a less arbitrary maximum such as 10.0, was that each compulsory figure was skated with six tracings.
