Year	current US$
1977	115183613.534615
1978	136657467.743949
1979	46379114.4869696
1980	21867796.4949428
1981	39174947.7136359
1982	78328274.0619503
1983	78684237.5433518
1984	94408496.876693
1985	64990348.9011611
1986	28596477.934028
1987	42532509.1626038
1988	121007703.743448
1989	122265984.145404
1990	158442457.602886
1991	214603025.040693
1992	-44436006.1450869
1993	-62618835.2155869
1994	-63504329.8936924
1995	-5203803.84224519
1996	-23412680.9171065
1997	-160016559.738963
1998	62657991.8134687
1999	-92078955.0156898
2000	-15690278.6111992
2001	-38257731.9001704
2002	-184386047.022682
2003	-163950929.897216
2004	-192026330.848704
2005	-306526707.070196
2006	-236719699.004662
2007	216076629.004064
2008	67590053.6694596
2009	-126171527.238718
2010	-24495525.0768781
2011	-599449339.548653
2012	-1003053536.41218
2013	-259906526.804435
2014	-428305072.885124
2015	-807464622.506423
2016	-933135046.990722
2017	-717373680.748073