Year	Annual Number
1970	176
1971	0
1972	5057
1973	0
1974	0
1975	0
1976	16
1977	1114
1978	25040
1979	565
1980	50
1981	3200
1982	0
1983	33
1984	0
1985	1
1986	1
1987	2
1988	1
1989	100
1990	40020
1991	0
1992	5
1993	24
1994	14
1995	0
1996	0
1997	2768
1998	22
1999	21
2000	1
2001	0
2002	230
2003	26800
2004	35
2005	625
2006	63
2007	0
2008	6