Year Annual Number 1970 10070 1971 0 1972 2510000 1973 0 1974 0 1975 10060 1976 508900 1977 30010 1978 18070 1979 0 1980 0 1981 118100 1982 70090 1983 13600 1984 100300 1985 0 1986 84410 1987 0 1988 0 1989 55390 1990 0 1991 250000 1992 0 1993 0 1994 540300 1995 0 1996 100000 1997 600200 1998 0 1999 0 2000 1106000 2001 0 2002 528100 2003 162800 2004 1033000 2005 8063 2006 6520 2007 222600 2008 533300