Year	Annual Number
1970	0
1971	0
1972	0
1974	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	0
1981	0
1982	0
1983	0
1984	0
1985	0
1986	0
1987	0
1988	39
1989	100
1990	118
1991	308
1992	731
1993	513
1994	0
1995	0
1996	378
1997	109
1998	239
1999	14
2000	22
2001	31
2002	0
2003	0
2004	46
2005	42
2006	8
2007	0
2008	0