Year	US Dollars
1960	-28266448000
1961	-13688764.74878
1962	-18398467.36678
1963	-4944523.78174
1964	31767612.33869
1965	35544090.81025
1966	39574955.79091
1967	35010925.86292
1968	33833303.4595
1969	30613940.95525
1970	33184046.2594
1971	35450417.91117
1972	-2600177.81863
1973	1646341.04984
1974	-45593820.20709
1975	-104498915.68263
1976	-209501565.40031
1977	-220545351.27854
1978	-171378862.96251
1979	-171335424.87918
1980	-211530272.03277
1981	-223492363.02975
1982	-334885557.63934
1983	-240971284.63068
1984	-200274606.64649
1985	-142644630.3508
1986	-185947440.67227
1987	-159176221.41357
1988	-122162630.56341
1989	-67805070.74357
1990	-153855460.57604
1991	-89480498.08532
1992	-9833599.91727
1993	24993770.17698
1994	42807829.25349
1995	86388966.46323
1996	59105087.37666
1997	-5354578.44099
1998	-111918758.88707
1999	-131824126.31137
2000	-198469550.68844
2001	-223253142.93248
2002	-184478420.66158
2003	-396437668.70699
2004	-750969811.32076
2005	-1130591353.16273
2006	-153298585.25689
2007	-445138903.12224
2008	-839153276.92932
2009	-580577460.30691
2010	-453079637.09494
2011	-329122648.21833
2012	-1381943714.79144
2013	-1271602662.90226
2014	-1435754643.64856
2015	-1703020628.94907
2016	-1242998319.04469
2017	-1151259351.14322