Season 1 ITV1 , 1972 Season 9 ITV1 , 1979 Season 10 ITV1 , 1980 Season 11 ITV1 , 1981 - 1982 Season 12 ITV1 , 1983 Season 13 ITV1 , 1984 Season 14 ITV1 , 1985 Season 15 ITV1 , 1986 Season 16 ITV1 , 1987 Season 17 ITV1 , 1988 - 1989 Season 18 ITV1 , 1989 - 1990 Season 19 ITV1 , 1990 - 1991 Season 20 ITV1 , 1991 - 1992 Season 21 ITV1 , 1992
, 1972