Year	current US$
1960	190600000
1961	177100000
1962	170200000
1963	101190000
1964	71100000
1965	59700000
1966	57200000
1967	54700000
1968	47700000
1969	36400000
1970	21740000
1971	27900000
1972	35587443.6841512
1973	61330424.0502206
1974	124272496.236805
1975	36369221.0537908
1976	23600000
1977	23148588.504019
1978	28355858.6829462
1979	67399668.0496894
1980	48725508.251952
1981	16970337.780304
1982	20500000
1983	16562817.3585958
1984	17200000
1985	12200000
1986	58512231.9670226
1987	11714186.6106768
1988	12113456.9579201
1989	15913141.6406024
1990	11414226.5723919
1991	7614304.30988857
1992	27518806.6515627
1993	37430695.743162
1994	78155912.5220222
1995	163360977.820457
1996	106782702.9225
1997	81584278.559589
1998	90623304.6109594
1999	188738166.783306
2000	137814239.250023
2001	49736273.1571601
2002	248935516.455669
2003	529445721.883466
2004	1337996807.7002
2005	1868587865.83723
2006	1659926271.61073
2007	1377921603.31558
2008	1399041059.55576
2009	1094176669.31606
2010	1036244170.70595
2011	192529339.697522
2012	192632614.669594
2013	192956941.623251
2014	181457168.977027
2015	173516490.886742
2016	168284353.053783
2017	177933851.813136