Question: When did the sport that Gregor Stähli played become an Olympic sport?

full_context: Document 1: Figure skating: Figure skating is a sport in which individuals, duos, or groups perform on figure skates on ice. It was the first winter sport included in the Olympics, in 1908. The four Olympic disciplines are men's singles, ladies' singles, pair skating, and ice dance. Non-Olympic disciplines include synchronized skating, Theater on Ice, and four skating. From novice through senior - level competition, skaters generally perform two programs (short and long) which, depending on the discipline, may include spins, jumps, moves in the field, lifts, throw jumps, death spirals, and other elements or moves.
Document 2: Sandro Stielicke: Sandro Stielicke (born November 30, 1986 in Rostock) is a German skeleton racer who has competed since 2005. His best World Cup finish was third at Altenberg, Germany in December 2008.
Document 3: Short track speed skating at the Winter Olympics: Short track speed skating has been a contest at the Winter Olympics since the 1992 Winter Games in Albertville, France. Prior to that, it was a demonstration sport at the 1988 games. The results from the 1988 demonstration competition is not included in the official Olympic statistics. The sport has been dominated by teams from Asia and North America, namely South Korea (IOC code KOR), China (CHN), Canada (CAN) and the United States (USA). Those four countries have won 134 of 168 medals awarded since 1992. South Korea leads the medal tally (and gold medal tally), with 42 medals including 21 golds since 1992. The majority of medals that South Korea won at the Winter Olympics came from short - track speed skating. Similarly, most of the China's Winter Olympics medals are from the sport.
Document 4: Alain Wicki: Alain Wicki is a Swiss skeleton racer who competed from the 1980s to the early first decade of the 21st century. He won a complete set of medals in the men's event at the FIBT World Championships with a gold in 1989, a silver in 1998, and a bronze in 1982.
Document 5: Skeleton at the Winter Olympics: Skeleton is a winter sport featured in the Winter Olympics where the competitor rides head - first and prone (lying face down) on a flat sled. It is normally run on an ice track that allows the sled to gain speed by gravity. It was first contested at the 1928 Winter Olympics in St. Moritz and again in 1948 Winter Olympics, after which it was discontinued as an Olympic sport. Skeleton was reintroduced at the 2002 Winter Olympics, with both men's and women's events, and has been held in each Winter Olympic competition since. Skeleton is so - named as the first metal sleds introduced in 1892 were said to resemble a human skeleton.
Document 6: Jürg Wenger: Jürg Wenger (born 1969) is a Swiss skeleton racer who competed from 1991 to 2003. He won a gold medal in the men's skeleton event at the 1995 FIBT World Championships in Lillehammer.
Document 7: Luge: The first organized meeting of the sport took place in 1883 in Switzerland. In 1913, the Internationale Schlittensportverband or International Sled Sports Federation was founded in Dresden, Germany. This body governed the sport until 1935, when it was incorporated in the Fédération Internationale de Bobsleigh et de Tobogganing (FIBT, International Bobsleigh and Tobogganing Federation). After it had been decided that luge would replace the sport of skeleton at the Olympic Games, the first World Championships in the sport were held in 1955 in Oslo (Norway). In 1957, the Fédération Internationale de Luge de Course (FIL, International Luge Federation) was founded. Luge events were first included in the Olympic Winter Games in 1964.
Document 8: Alexander Berner: Alexander Berner (born 1901, date of death unknown) was a Swiss skeleton racer who competed in the late 1920s. He finished fifth in the men's skeleton event at the 1928 Winter Olympics in St. Moritz.
Document 9: Felix Poletti: Felix Poletti (born July 23, 1965) is a Swiss skeleton racer who has competed since 1995. He won a bronze medal in the men's skeleton event at the 1998 FIBT World Championships in St. Moritz.
Document 10: Gregor Stähli: Gregor Stähli (born 28 February 1968 in Zürich) is a Swiss skeleton racer who has competed since 1989. He won two bronze Winter Olympic medals in the men's skeleton, earning them in 2002 and 2006.
Document 11: Alexander Müller (skeleton racer): Alexander Müller is an Austrian skeleton racer who competed from 1989 to 2000. He won a bronze medal in the men's skeleton event (tied with Jimmy Shea of the United States) at the 2000 FIBT World Championships in Igls.
Document 12: Winter Olympic Games: The Olympic Winter Games (official name) (French: Jeux olympiques d'hiver) is a major international sporting event held once every four years, for sports practised on snow and ice. The first Winter Olympics, the 1924 Winter Olympics, was held in Chamonix, France. The original five sports (broken into nine disciplines) were bobsleigh, curling, ice hockey, Nordic skiing (consisting of the disciplines military patrol, cross-country skiing, Nordic combined, and ski jumping), and skating (consisting of the disciplines figure skating and speed skating). The Games were held every four years from 1924 to 1936, interrupted in 1940 and 1944 by World War II, and resumed in 1948. Until 1992 the Winter and Summer Olympic Games were held in the same years, but in accordance with a 1986 decision by the International Olympic Committee (IOC) to place the Summer and Winter Games on separate four - year cycles in alternating even - numbered years, the next Winter Olympics after 1992 was in 1994.
Document 13: Snowboarding at the Winter Olympics: Snowboarding is a sport at the Winter Olympic Games. It was first included in the 1998 Winter Olympics in Nagano, Japan. Snowboarding was one of five new sports or disciplines added to the Winter Olympic program between 1992 and 2002, and was the only one not to have been a previous medal or demonstration event. In 1998, four events, two for men and two for women, were held in two specialities: the giant slalom, a downhill event similar to giant slalom skiing; and the half - pipe, in which competitors perform tricks while going from one side of a semi-circular ditch to the other. Canadian Ross Rebagliati won the men's giant slalom and became the first athlete to win a gold medal in snowboarding. Rebagliati was briefly stripped of his medal by the International Olympic Committee (IOC) after testing positive for marijuana. However, the IOC's decision was reverted following an appeal from the Canadian Olympic Association. For the 2002 Winter Olympics, giant slalom was expanded to add head - to - head racing and was renamed parallel giant slalom. In 2006, a third event, the snowboard cross, was held for the first time. In this event, competitors race against each other down a course with jumps, beams and other obstacles. On July 11, 2011, the International Olympic Committee's Executive Board approved the addition of Ski and Snowboard Slopestyle to the Winter Olympics roster of events, effective in 2014. The decision was announced via press conference from the IOC's meeting in Durban, South Africa. A fifth event, parallel slalom, was added only for 2014. Big air was added for 2018.
Document 14: Figure skating at the Olympic Games: Figure skating was first contested in the Olympic Games at the 1908 Summer Olympics. Since 1924, the sport has been a part of the Winter Olympic Games.
Document 15: List of Olympic medalists in snowboarding: Snowboarding is a sport that has been contested at the Winter Olympic Games since the 1998 Winter Olympics in Nagano, Japan. Snowboarding was one of five new sports or disciplines added to the Winter Olympic programme between 1990 and 2002, and was the only one not to have been a previous medal or demonstration event. In 1998, four events, two for men and two for women, were held in two specialities: the giant slalom, a downhill event similar to giant slalom skiing; and the half - pipe, in which competitors perform tricks while going from one side of a semi-circular ditch to the other. Canadian Ross Rebagliati won the men's giant slalom and became the first athlete to win a gold medal in snowboarding. Rebagliati was briefly stripped of his medal by the International Olympic Committee (IOC) after testing positive for marijuana. However, the IOC's decision was reverted following an appeal from the Canadian Olympic Association. For the 2002 Winter Olympics, the giant slalom was dropped in favour of the parallel giant slalom, an event that involves head - to - head racing. In 2006, a third event, the snowboard cross, was held for the first time. In this event, competitors race against each other down a course with jumps, beams and other obstacles.
ground_truth: 1928
sub_queries: Gregor Stähli >> sport Answer: skeleton
when did the skeleton become an olympic sport Answer: 1928