Year	Annual Number
1970	70
1971	0
1972	91
1973	0
1974	0
1975	7
1976	16
1977	10
1978	70
1979	0
1980	0
1981	107
1982	92
1983	42
1984	68
1985	0
1986	99
1987	0
1988	0
1989	46
1990	0
1991	36
1992	0
1993	0
1994	212
1995	0
1996	9
1997	174
1998	0
1999	0
2000	153
2001	0
2002	23
2003	89
2004	395
2005	78
2006	4
2007	84
2008	105