Year	Annual Number
1970	0
1971	0
1972	0
1973	0
1974	0
1975	0
1976	20
1977	0
1978	0
1979	1
1980	0
1981	0
1982	0
1983	0
1984	0
1985	0
1986	0
1987	0
1988	19
1989	0
1990	5
1991	0
1992	0
1993	413
1994	151
1995	14
1996	7
1997	0
1998	0
1999	34
2000	0
2001	0
2002	11
2003	10
2004	0
2005	8
2006	4
2007	6
2008	67