Season 1 ABC , 1975 Season 2 ABC , 1976 Season 3 ABC , 1977 Season 4 ABC , 1978 Season 5 ABC , 1979 Season 6 ABC , 1980 Season 7 ABC , 1981 Season 11 ABC , 1985 Season 12 ABC , 1986 Season 14 1988-1989 ABC , 1988 - 1989
, 1988 - 1989
