Year Annual Number 1970 0 1971 0 1972 0 1973 0 1974 0 1975 145000 1976 0 1977 0 1978 100000 1979 0 1980 0 1981 0 1982 0 1983 132000 1984 0 1985 0 1986 0 1987 0 1988 2500000 1989 0 1990 0 1991 0 1992 0 1993 2021 1994 5973 1995 0 1996 120600 1997 100000 1998 1000000 1999 280900 2000 0 2001 97000 2002 100000 2003 325100 2004 0 2005 160800 2006 167000 2007 565500 2008 92810