Year	current US$
1977	6459872.5272912
1978	11718195.4618897
1979	10941368.5738008
1980	14274462.0755436
1981	10339663.6656296
1982	19055814.7986323
1983	31189453.8267297
1984	27052883.5204658
1985	28788951.7411752
1986	22163248.5934206
1987	16673557.7267321
1988	32322080.6310834
1989	11570871.8681528
1990	37488527.3696534
1991	31935037.5527822
1992	54911267.1492412
1993	77522776.8016756
1994	85116921.7736893
1995	-38620777.5525101
1996	-35224270.6076079
1997	-34667563.8715187
1998	-40209497.1315005
1999	-44354574.2373658
2000	-46485200.4833343
2001	-68247557.3190007
2002	-74224624.610209
2003	-59888900.0376722
2004	-71827255.7930694
2005	-10204109.4530492
2006	7873322.17342445
2007	-57443969.1136892
2008	-40066376.1692224
2009	115113728.636919
2010	97864026.7535241
2011	79068832.8882297
2012	118706926.6261
2013	124763947.90315
2014	23139316.3388024
2015	90946019.0253045
2016	-82903476.0820961