Year	Annual Number
1970	0
1971	0
1972	0
1973	474
1974	0
1975	0
1976	338
1977	848
1978	393
1979	13
1980	75
1981	82
1982	68
1983	39
1984	39
1985	0
1986	0
1987	0
1988	196
1989	20
1990	0
1991	24
1992	1446
1993	15
1994	316
1995	1063
1996	111
1997	171
1998	1000
1999	34
2000	0
2001	210
2002	37
2003	266
2004	5
2005	636
2006	400
2007	526
2008	82