Year	US Dollars
1972	889820.35928
1973	4217434.72678
1974	39049518.89228
1975	21915172.14295
1976	8509104.2405
1977	6819693.94544
1978	3933844.56907
1979	720992.6224
1980	-647688.45366
1981	-17957251.20662
1982	-16063292.42317
1983	-12331531.53153
1984	-5074506.36244
1985	-5292269.0132
1986	-3237433.15508
1987	-27104887.27069
1988	-27259942.18298
1989	-29836944.48838
1990	-38868628.52236
1991	-34582255.80308
1992	-48850249.70623
1993	-38802121.58303
1994	-34251644.97734
1995	-47316530.76353
1996	-52520541.51342
1997	-48480332.49221
1998	-41283327.05114
1999	-51840000
2000	-54725765.30612
2001	-51813902.96886
2002	-65409649.02749
2003	-68055580.77696
2004	-80692013.5314
2005	-108720274.91409
2006	-86596385.54217
2007	-94079323.90595
2008	-101990102.33182
2009	-93561066.91624
2010	-102049623.92222
2011	-124794120.68076
2012	-149633464.4854
2013	-150169530.79745
2014	-146745988.82279
2015	-158365261.81354
2016	-153434433.54148
2017	-167688534.64132