Year	Annual Number
1970	0
1971	0
1972	0
1973	0
1974	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	256
1981	58
1982	0
1983	0
1984	0
1985	0
1986	265
1987	865
1988	90
1989	0
1990	0
1991	56
1992	63
1993	781
1994	39
1995	27
1996	49
1997	13
1998	157
1999	81
2000	10
2001	476
2002	61
2003	0
2004	40
2005	109
2006	14
2007	12
2008	22