Year	Annual Number
1970	0
1971	0
1972	120000
1973	6209
1974	0
1975	23000
1976	0
1977	0
1978	0
1979	35950
1980	35270
1981	4700
1982	0
1983	211200
1984	0
1985	122000
1986	3001
1987	3370
1988	0
1989	0
1990	6000
1991	0
1992	2001
1993	160000
1994	0
1995	0
1996	0
1997	3525
1998	0
1999	1784
2000	0
2001	1
2002	0
2003	30020
2004	5016
2005	0
2006	168
2007	70
2008	7