Year	Annual Number
1970	150600
1971	2400
1972	0
1973	30000
1974	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	0
1981	0
1982	700300
1983	200000
1984	0
1985	0
1986	0
1987	10000
1988	0
1989	30040
1990	0
1991	0
1992	205000
1993	0
1994	0
1995	0
1996	0
1997	49250
1998	0
1999	0
2000	66
2001	9588
2002	54660
2003	7905
2004	0
2005	0
2006	57690
2007	0
2008	289200