Year	Annual Number
1970	10180
1971	0
1972	28520
1973	0
1974	0
1975	0
1976	16
1977	421800
1978	65100
1979	20790
1980	150
1981	37200
1982	0
1983	7515
1984	0
1985	7081
1986	1905
1987	3977
1988	16560
1989	1817
1990	772400
1991	1501
1992	4055
1993	5076
1994	16660
1995	0
1996	0
1997	226000
1998	9312
1999	7061
2000	3016
2001	1000
2002	147400
2003	323800
2004	533
2005	117500
2006	168600
2007	0
2008	20720