Year	2007 US$
1967	1789000000
1968	1956000000
1970	347100000
1971	601500000
1972	140600000
1973	155800000
1975	197100000
1976	171600000
1977	167100000
1978	156500000
1979	155600000
1980	213600000
1981	700700000
1982	1631000000
1983	2209000000
1984	2460000000
1985	2973000000
1986	4413000000
1987	4759000000
1988	4211000000
1989	3378000000
1990	2125000000
1991	3073000000
1992	2178000000
1993	1010000000
1994	494700000
1995	634600000
1996	485600000
1997	421500000
1998	208200000
1999	416100000
2000	587400000
2001	562300000
2002	397100000
2003	418000000
2004	634600000
2005	832700000
2006	810400000
2007	643600000