Year	Annual Number
1970	0
1971	0
1972	0
1973	0
1974	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	41
1981	656
1982	0
1983	0
1984	0
1985	0
1986	261
1987	0
1988	36
1989	0
1990	0
1991	0
1992	0
1993	609
1994	56
1995	0
1996	0
1997	41
1998	12
1999	536600
2000	0
2001	504
2002	26
2003	2608
2004	0
2005	58
2006	0
2007	1650000
2008	0