Title: Tug of war
Content:  There are tug of war clubs in many countries, and both men and women participate. The sport was part of the Olympic Games from 1900 until 1920, but has not been included since. The sport is part of the World Games. The Tug of War International Federation (TWIF), organises World Championships for nation teams biannually, for both indoor and outdoor contests, and a similar competition for club teams. In England the sport was formally governed by the AAA until 1984, but is now catered for by the Tug of War Association (formed in 1958), and the Tug of War Federation of Great Britain (formed in 1984). In Scotland, the Scottish Tug of War Association was formed in 1980. The sport also features in Highland Games. Between 1976 and 1988 Tug of War was a regular event during the television series Battle of the Network Stars. Teams of celebrities representing each major network competed in different sporting events culminating into the final event, the Tug of War. Lou Ferrigno's epic tug-o'-war performance in May 1979 is considered the greatest feat in 'Battle' history.
Title: Tug of war at the Summer Olympics
Content:  Tug of war was contested as a team event in the Summer Olympics at the Games of every Olympiad from 1900 to 1920. Originally the competition was entered by groups called clubs. A country could enter more than one club in the competition, making it possible for one country to earn multiple medals. This happened in 1904, when the United States won all three medals, and in 1908 when the podium was occupied by three British teams. Sweden was also among the top countries with two medals, one as a member of the mixed team. During its time as an Olympic sport, it was considered to be part of the Olympic athletics programme, although the sports of tug of war and athletics are now considered distinct.
Title: Tug of war at the 1920 Summer Olympics
Content:  The tug of war contest at the 1920 Summer Olympics was held on August 17, 1920, and on August 18, 1920. All medals were decided by using the Bergvall system. This was the last time the tug of war was in the Olympic program.
Title: Athletics at the Summer Olympics
Content:  The events contested have varied widely. From 1900 to 1920, tug of war was considered to be part of the Olympic athletics programme, although the sports of tug of war and athletics are now considered distinct.
Title: Tug of war at the 1900 Summer Olympics
Content:  The modern Olympic Games were first held in Athens in 1896, and travelled to Paris four years later as part of the 1900 Exposition Universelle world's fair. The second Games featured a greatly expanded range of events from the first, up from 43 to 95. Among the events added in 1900 was the tug of war. Two tug of war teams were entered for the Paris tournament: Racing Club de France represented the host nation, along with a team from the United States which was composed of six athletes that were taking part in various other events during the Games. However, the American 
Title: City of London Police
Content:   Teams of the City of London Police have participated in the Olympic games three times in the tug of war tournament. At the 1908 Summer Olympics they won the gold medal, beating a team of the Liverpool Police in the final. In 1912 the team was beaten in the final by one of the Stockholm Police. At the 1920 Summer Olympics the team regained its title, beating the Netherlands. This was the last time tug of war was an Olympic sport, which means the City of London Police is still the reigning Olympic champion.
Title: Tug of war at the 1906 Intercalated Games
Content:  At the 1906 Summer Olympics in Athens, a tug of war event was contested. Now called the Intercalated Games, the 1906 Games are no longer considered as an official Olympic Games by the International Olympic Committee.
Title: Great Britain at the 1920 Summer Olympics
Content: Quarterfinals Semifinals Final Final rank: Gold Great Britain competed in the Olympic tug of war tournament for the third time in 1920, the final appearance of the sport in the Olympics. Along with Sweden and the United States, Great Britain's three appearances in the five Olympic tug of war tournaments were the most of any nation. The Bergvall System was used in 1920. Great Britain won all three of its matches, taking the gold medal to become the only country to win two Olympic golds in the tug of war. All matches were best-of-three pulls.    
Title: 1908 Summer Olympics
Content:  22 sports, representing 110 events in 24 sporting disciplines, were contested. Swimming, diving and water polo are considered three disciplines of the same sport, aquatics. At the time, tug-of-war was part of athletics and the two different football codes (association and rugby (union)) were listed together. The International Olympic Committee now considers tug-of-war a separate sport, as well as referring to association football as simply "football" and to rugby union as "rugby". In one of seven cycling events (cycling sprint) no medals were awarded. The sailing program was open for a total of five sailing classes, but actually only four sailing events were contested. The number of events in each discipline is noted in parentheses. • Aquatics • * • * • * • • • • • • • • • • • • • • • • • • • • • • *Wrestling Freestyle (5) • *Wrestling Greco-Roman (4)
Title: Tug of war at the Summer Olympics
Content:  Teams consisted of 6 members in 1900 (Denmark and Sweden competed together), 5 members in 1904, and 8 members in the last three appearances of the sport.

Question: when was the last time tug-of-war was an official olympic sport?
Answer: 1920.