Year	Annual Number
1970	0
1971	0
1972	0
1974	0
1975	0
1976	449
1977	0
1978	0
1979	0
1980	0
1981	0
1982	0
1983	0
1984	0
1985	0
1986	0
1987	60
1988	41580
1989	0
1990	0
1991	12
1992	0
1993	0
1994	0
1995	0
1996	2500
1997	0
1998	25520
1999	4316
2000	2549
2001	0
2002	1330
2003	205
2004	8212
2005	8104
2006	29910
2007	8223
2008	227