Year	Annual Number
1970	0
1971	0
1972	0
1973	0
1974	0
1975	0
1976	70000
1977	16010
1978	1009
1979	0
1980	0
1981	20000
1982	0
1983	0
1984	0
1985	28010
1986	0
1987	0
1988	47280
1989	0
1990	350000
1991	0
1992	0
1993	34800
1994	43020
1995	93900
1996	115000
1997	65350
1998	0
1999	147300
2000	30070
2001	39500
2002	4022
2003	110100
2004	0
2005	242600
2006	435100
2007	245400
2008	116500