Year Annual Number 1970 0 1971 0 1972 0 1973 0 1974 0 1975 0 1976 0 1977 0 1978 0 1979 1118 1980 1165000 1981 0 1982 0 1983 0 1984 0 1985 0 1986 0 1987 0 1988 870100 1989 0 1990 0 1991 0 1992 0 1993 0 1994 1588000 1995 0 1996 181 1997 0 1998 12220 1999 0 2000 0 2001 0 2002 254 2003 181 2004 324900 2005 28050 2006 15000 2007 115200 2008 247000