3400
U.K. (United Kingdom) 1991:
31300
U.K. (United Kingdom) 1992:
30000
U.K. (United Kingdom) 1993:
30000
U.K. (United Kingdom) 1994:
30000
U.K. (United Kingdom) 1995:
30000
U.K. (United Kingdom) 1996:
30000
U.K. (United Kingdom) 1997:
tba
U.K. (United Kingdom) 1998: