Year	US Dollars
1960	296713739.70992
1961	126264667.45067
1962	60988599.24213
1963	44891088.46204
1964	47815007.18672
1965	134271298.83706
1966	131619985.62655
1967	80499509.99608
1968	119083137.33176
1969	375311119.82229
1970	175208153.66523
1971	63264685.64689
1972	-65723045.8221
1973	437266811.27983
1974	28427485.35582
1975	47630746.16922
1976	1165780256.53132
1977	998019948.80754
1978	906694084.62867
1979	1879638959.97075
1980	602676834.03004
1981	-1564322295.03928
1982	-2356987197.05404
1983	-1743055960.0224
1984	633871522.4441
1985	1592444945.63029
1986	1683428410.9398
1987	4463407763.13701
1988	3600122460.66901
1989	2356022556.1134
1990	899848423.23191
1991	-1798807099.21443
1992	802607295.71603
1993	-66819470.88303
1994	-1194177716.81145
1995	-3490430622.00957
1996	1397964862.07171
1997	914188373.90871
1998	15873420301.6714
1999	19828157894.7368
2000	18019473684.21049
2001	16181842105.2632
2002	17400526315.7895
2003	21700526315.7895
2004	25414473684.21049
2005	31496395658.94749
2006	35456354615.3427
2007	38459972073.5397
2008	51542841327.41769
2009	41006829479.3588
2010	40587997888.91989
2011	46400653594.7712
2012	33828023828.0238
2013	27598463930.9404
2014	31354456292.5846
2015	22683907310.2036
2016	19837523804.93209
2017	22100037205.8413