Year	Annual Number
1970	0
1971	0
1972	0
1973	0
1974	0
1975	0
1976	477900
1977	4187
1978	0
1979	86270
1980	20000
1981	2988
1982	23830
1983	100
1984	1949
1985	17
1986	0
1987	32230
1988	0
1989	23010
1990	9317
1991	17220
1992	102100
1993	0
1994	261100
1995	92030
1996	38810
1997	3125
1998	6982
1999	16920
2000	270300
2001	12510
2002	11860
2003	3250
2004	140900
2005	106900
2006	3186000
2007	619600
2008	10740