Year	Annual Number
1970	0
1971	0
1972	0
1973	0
1974	32
1975	0
1976	0
1977	0
1978	4
1979	0
1980	0
1981	0
1982	0
1983	0
1984	0
1985	0
1986	23
1987	127
1988	0
1989	21
1990	0
1991	0
1992	0
1993	109
1994	0
1995	28
1996	0
1997	22
1998	0
1999	0
2000	16
2001	4
2002	19
2003	0
2004	3
2005	5
2006	18
2007	0
2008	9