Year	constant 2015 US$
1960	1430000
1961	2590000
1962	3650000
1963	4490000
1964	5530000
1965	4660000
1966	16580000
1967	15180000
1968	19170000
1969	24650000
1970	22700000
1971	29900000
1972	35760000
1973	40250000
1974	69950000
1975	47740000
1976	109890000
1977	54280000
1978	58350000
1979	89370000
1980	86640000
1981	67450000
1982	59730000
1983	64720000
1984	62370000
1985	56390000
1986	52300000
1987	92160000
1988	64160000
1989	65000000
1990	73060000
1991	73080000
1992	57300000
1993	53930000
1994	54210000
1995	54970000
1996	41530000
1997	38440000
1998	60520000
1999	54690000
2000	70520000
2001	55320000
2002	45920000
2003	47180000
2004	47900000
2005	47090000
2006	56940000
2007	58160000
2008	93910000
2009	106320000
2010	99480000
2011	71340000
2012	79780000
2013	76050000
2014	86410000
2015	188760000
2016	129060000
2017	128550000