Year Total 1971 1058000000 1972 1193000000 1973 1322000000 1974 1393000000 1975 1529000000 1976 1650000000 1977 1928000000 1978 2044000000 1979 2098000000 1980 2337000000 1981 2425000000 1982 2562000000 1983 2968000000 1984 3005000000 1985 3200000000 1986 3558000000 1987 3895000000 1988 4366000000 1989 4744000000 1990 5289000000 1991 5719000000 1992 6033000000 1993 6694000000 1994 7176000000 1995 7519000000 1996 8111000000 1997 8040000000 1998 9112000000 1999 8725000000 2000 8957000000 2001 9114000000 2002 9279000000 2003 9549000000 2004 9484000000 2005 9950000000 2006 9844000000 2007 10120000000 2008 10310000000