Year	Annual Number
1970	0
1971	0
1972	0
1973	0
1974	26
1975	0
1976	0
1977	4
1978	26
1979	0
1980	0
1981	104
1982	0
1983	0
1984	0
1985	0
1986	0
1987	506
1988	25
1989	0
1990	0
1991	0
1992	0
1993	12
1994	0
1995	207
1996	34
1997	0
1998	0
1999	27
2000	93
2001	5
2002	16
2003	1
2004	0
2005	0
2006	12
2007	0
2008	11