Year	constant 2015 US$
1960	114440000
1961	233350000
1962	114880000
1963	236450000
1964	302480000
1965	370250000
1966	338270000
1967	259230000
1968	182000000
1969	162680000
1970	155750000
1971	229150000
1972	264750000
1973	239560000
1974	192540000
1975	239710000
1976	240350000
1977	266470000
1978	222870000
1979	252370000
1980	72610000
1981	53620000
1982	22660000
1983	33650000
1984	16750000
1985	39890000
1986	4200000
1987	80740000
1988	119540000
1989	238500000
1990	183250000
1991	708640000
1992	283700000
1993	313320000
1994	309760000
1995	253210000
1996	203990000
1997	306200000
1998	221180000
1999	195990000
2000	201260000
2001	630540000
2002	1797060000
2003	1928200000
2004	2592760000
2005	3166480000
2006	3201560000
2007	5033950000
2008	4754710000
2009	6265080000
2010	6357280000
2011	6434100000
2012	6233970000
2013	4798270000
2014	4603680000
2015	4271360000
2016	4069210000
2017	3743840000