Source: BT Annual Reports.
1980 1981 1982 1983 1984 1985 Residential 13,937 14,671 15,159 15,546 16,044 16,596 Business 3,416 3,503 3,568 3,640 3,768 3,932 1986 1987 1988 1989 1990 1991 Residential 17,120 17,549 18,106 18,703 19,246 19,573 Business 4,141 4,359 4,558 5,307 5,551 5,795 1992 1993 1994 1995 Residential 19,729 20,144 Business 5,866 5,970