Year	Annual Number
1970	0
1971	0
1972	0
1973	0
1974	0
1975	0
1976	0
1977	0
1978	50
1979	0
1980	0
1981	43060
1982	0
1983	0
1984	0
1985	0
1986	0
1987	0
1988	0
1989	199500
1990	36
1991	1894000
1992	386500
1993	213900
1994	15020
1995	27
1996	343400
1997	50590
1998	0
1999	0
2000	41220
2001	150
2002	30200
2003	5000
2004	9064
2005	3510
2006	0
2007	0
2008	1000