Year	Annual Number
1970	0
1971	1601
1972	0
1973	277
1974	2401
1975	2059
1976	2530
1977	129
1978	2907
1979	12600
1980	370
1981	0
1982	905
1983	2584
1984	0
1985	614
1986	46
1987	0
1988	104
1989	1664
1990	0
1991	204
1992	442
1993	1326
1994	0
1995	0
1996	0
1997	256
1998	0
1999	495
2000	0
2001	0
2002	0
2003	3537
2004	0
2005	0
2006	0
2007	0
2008	209