Year Annual Number 1970 10000000 1971 0 1972 0 1973 0 1974 0 1975 0 1976 0 1977 0 1978 0 1979 5000000 1980 0 1981 0 1982 0 1983 20000000 1984 0 1985 0 1986 0 1987 750000 1988 0 1989 0 1990 0 1991 0 1992 0 1993 0 1994 0 1995 0 1996 0 1997 0 1998 10000000 1999 0 2000 0 2001 1000000 2002 0 2003 0 2004 0 2005 0 2006 0 2007 1000000 2008 0