Year	US Dollars
1981	-1089508866.66667
1982	-974987233.33333
1983	-976184300
1984	-753278150
1985	-906893375
1986	-1483275100
1987	-1252314200
1988	-1204029033.33333
1989	-1122831166.66667
1990	-565229200
1991	-677232000
1992	-97894086.85446
1993	-85121072.89909
1994	-91618008.33495
1995	-14825363.2331
1996	-93196784.84618
1997	63076543.75372
1998	-131156754.35758
1999	-126090235.82302
2000	-157950192.91425
2001	-192502943.66162
2002	-238308563.52653
2003	-248791319.97139
2004	-194301582.74838
2005	-122203961.64536
2006	203359826.38625
2007	57107720.70559
2008	-740236927.52179
2009	-332684790.18219
2010	-718377804.0862
2011	-2278925241.39169
2012	-2759021641.45023
2013	-2834942809.61529
2014	-589845507.49704
2015	117986948.95197
2016	535901050.41329
2017	270332262.79842