Year	US Dollars
1980	-581746913.58025
1981	-559031161.47309
1982	-646605820.10582
1983	-538748756.2189
1984	-479898584.90566
1985	-383527777.77778
1986	-498571782.17822
1987	-582499828.00138
1988	-611880861.60884
1989	-704093569.60666
1990	-700721450.86643
1991	-1141677797.14186
1992	-998488486.26534
1993	-978164941.40872
1994	-978344602.49415
1995	-1102137818.63224
1996	-964469421.00463
1997	-932972547.55882
1998	-939063437.92633
1999	-1556536872.5098
2000	-1341041163.18168
2001	-628447274.87007
2002	-1589721268.68823
2003	-1420671297.56163
2004	-1322312736.64492
2005	-1234798421.57755
2006	-895046565.46251
2007	-850023238.89428
2008	-1130665884.79297
2009	-1233864075.90585
2010	-1493801216.72198
2011	-2820716567.58728
2012	-6697037016.77852
2013	-8592081962.25763
2014	-8718696377.02654
2015	-5885853575.93947
2016	-4126331908.29008
2017	-3992943377.89724