Year	Annual Number
1970	0
1971	0
1972	0
1973	0
1974	18030
1975	0
1976	0
1977	90010
1978	178000
1979	0
1980	15000
1981	0
1982	30000
1983	50250
1984	3000
1985	475
1986	310000
1987	20020
1988	0
1989	0
1990	0
1991	0
1992	40050
1993	0
1994	0
1995	0
1996	0
1997	190100
1998	0
1999	1600
2000	7040
2001	357300
2002	5222
2003	57600
2004	0
2005	0
2006	126600
2007	824600
2008	0