Year	US Dollars
1960	-370377411.09675
1961	-239840629.788
1962	-329924345.86287
1963	-427155489.05957
1964	-256539872.87107
1965	-224737237.23724
1966	-384056902.7788
1967	-513085908.62043
1968	-764467739.02042
1969	-909147695.7246
1970	-871973209.68573
1971	-1023764943.10817
1972	-525846929.16592
1973	-518678449.48785
1974	-2161099710.73256
1975	-1885330578.5124
1976	-843801652.89256
1977	-722314049.58678
1978	-2241942148.76033
1979	-4958264462.80992
1980	-5634723342.60738
1981	-5250429496.49795
1982	-4305137604.63971
1983	-1798775378.66581
1984	859202461.59955
1985	1443989793.33808
1986	4866299846.84327
1987	9551527529.57195
1988	13138064445.5685
1989	5267476841.50956
1990	-1623572962.58618
1991	-6787891184.29127
1992	-823032088.64409
1993	2623244920.07924
1994	-1713610056.63076
1995	-5105734697.31739
1996	-17553608055.193
1997	-3785070798.5998
1998	40383748144.7654
1999	27620665870.3588
2000	11628970078.5174
2001	8282713266.56287
2002	9135314006.18661
2003	13687615914.6029
2004	29286662242.8666
2005	21869773239.7099
2006	7903932852.28546
2007	12645259822.0105
2008	-107617943.95833
2009	42272638280.87681
2010	34858714202.7973
2011	17975586039.0957
2012	34168661983.9591
2013	65011381894.3166
2014	74149294066.78769
2015	96257771353.6797
2016	96992899377.07762
2017	82702375726.78432