Year	Annual Number
1970	0
1971	0
1972	0
1973	5
1974	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	0
1981	0
1982	620
1983	0
1984	0
1985	0
1986	0
1987	84
1988	0
1989	10
1990	0
1991	0
1992	0
1993	0
1994	10
1995	31
1996	0
1997	0
1998	0
1999	12
2000	36
2001	0
2002	0
2003	0
2004	0
2005	0
2006	0
2007	11
2008	21