Year	current US$
1981	143251289742.476
1982	120626442751.604
1983	73473493738.7724
1984	44641942598.8937
1985	35732086215.2396
1986	29301351103.3715
1987	27178712746.7003
1988	23826239046.6866
1989	28317988883.7837
1990	31894387466.5972
1991	27699042861.73
1992	23374253708.8058
1993	12592441172.4999
1994	13749449064.5385
1995	18306818703.7002
1996	19730134700.8927
1997	22481923948.1974
1998	18165266088.3067
1999	27455479600.5116
2000	35176108532.5603
2001	25215828470.3008
2002	27772528085.395
2003	28594326470.9751
2004	41124282069.8861
2005	63781050155.4167
2006	117822852775.021
2007	73898294308.0138
2008	107835598307.169
2009	72665332574.9142
2010	88372168175.1778
2011	98483280932.3324
2012	146506910676.972
2013	93212566836.1344
2014	119724121452.268
2015	78243663447.9138
2016	64099890944.1049
2017	68594053240.998
