Year	Annual Number
1970	1438
1971	0
1972	22310
1973	0
1974	0
1975	3259
1976	200
1977	97
1978	300
1979	0
1980	0
1981	0
1982	185
1983	613
1984	0
1985	366
1986	0
1987	1000
1988	0
1989	1860
1990	0
1991	0
1992	1633
1993	0
1994	4018
1995	0
1996	0
1997	80
1998	0
1999	0
2000	0
2001	0
2002	0
2003	0
2004	0
2005	0
2006	0
2007	0
2008	0