Year	Annual Number
1970	0
1971	0
1972	0
1974	0
1975	0
1976	0
1977	756
1978	17
1979	0
1980	0
1981	0
1982	0
1983	0
1984	0
1985	0
1986	0
1987	0
1988	0
1989	0
1990	221
1991	0
1992	70
1993	0
1994	0
1995	0
1996	1703
1997	0
1998	11200
1999	412
2000	665
2001	0
2002	14
2003	0
2004	130
2005	0
2006	0
2007	0
2008	0