Question: How long was Raymond William "Ray" Butt's most famous television show originally broadcasted?

Context paragraphs:
Raymond Burr: Raymond William Stacy Burr (May 21, 1917September 12, 1993) was a Canadian-American actor, primarily known for his title roles in the television dramas "Perry Mason" and "Ironside".  He was prominently involved in multiple charitable endeavors, such as working on behalf of the United Service Organizations.

Raymond Firth: Sir Raymond William Firth, CNZM, FBA (25 March 1901 – 22 February 2002) was an ethnologist from New Zealand.  As a result of Firth's ethnographic work, actual behaviour of societies (social organization) is separated from the idealized rules of behaviour within the particular society (social structure).  He was a long serving Professor of Anthropology at London School of Economics, and is considered to have singlehandedly created a form of British economic anthropology.

Only Fools and Horses: Only Fools and Horses is a British television sitcom created and written by John Sullivan.  Seven series were originally broadcast on BBC One in the United Kingdom from 1981 to 1991, with sixteen sporadic Christmas specials aired until the end of the show in 2003.  Episodes are regularly repeated on UKTV comedy channel Gold, Yesterday and occasionally repeated on BBC One.

Thee Mr. Duran Show: Thee Mr. Duran Show is a variety television show.  The show is hosted by Richard Duran, and currently films at the LVTV Channel 3 Studio on the campus of the University of La Verne in La Verne, California.  Episodes premiere live online at the show's official website, in addition to airing on Public-access television cable TV Channel 3 in the La Verne and San Dimas area, in select viewing areas on Time Warner Cable.  The show originally debuted at East L.A. Community Television (formerly Buenavision Cable) in November 2000, before relocating to KCAT in March 2004, whose studio was located on the campus of Glen A. Wilson High School.  Thee Mr. Duran Show made its debut on LVTV in October 2009, following the closing of the KCAT Television operations in March 2009.  Thee Mr. Duran Show routinely features one live band, performing for approximately 30 minutes, and one to two speaking guests.  The use of "Thee" in the title is an homage to the 1960s Chicano rock bands out of East L.A., where Duran grew up, such as Thee Midniters.

Ray Gravell: Raymond William Robert "Ray" Gravell (12 September 1951 – 31 October 2007) was a Welsh rugby union centre who played club rugby for Llanelli RFC.

Ray Aston: Raymond William "Ray" Aston (24 September 1943 – 23 May 1988) was an Australian politician.  He was the Liberal member for Vaucluse in the New South Wales Legislative Assembly from 1986 till his early death.

La casa de los líos: La casa de los líos (in English, "The house of trouble") was a famous television show on TV channel A3 in Spain for 4 years, 1996 until 2000.

Ray Frankowski: Raymond William "Ray" Frankowski (September 14, 1919 – November 27, 2001) was a guard in the National Football League.

Ray Hackett: Ray Hackett "(né" Raymond William Hackett; 5 November 1909 Carlin, Nevada – 29 March 1987 Santa Rosa, California) was an American radio broadcast and dance orchestra leader who flourished from 1928, while attending the University of Nevada, Reno, to the mid 1970s in the San Francisco Bay Area, where he spent most of his professional career.

Ray Butt: Raymond William "Ray" Butt (25 June 1935 – 12 July 2013) was a British television producer and director best known for his work on "Only Fools and Horses".

Supporting paragraphs: Ray Butt Only Fools and Horses
Answer: from 1981 to 1991