Year	US Dollars, Monthly Level
1960-01-01	-157483207.8549990
1961-01-01	-268022950.3448570
1962-01-01	-180498194.0975250
1963-01-01	-177181276.9883480
1964-01-01	-299979089.5608130
1965-01-01	-63190095.1599679
1966-01-01	-329332376.2204140
1967-01-01	-118323814.4066130
1968-01-01	-34614030.1610534
1969-01-01	25104196.1110542
1970-01-01	157822809.5395430
1971-01-01	19819480.9477706
1972-01-01	645198507.1973910
1973-01-01	378883761.1434080
1974-01-01	-1573693375.9884000
1975-01-01	-1986383991.5610200
1976-01-01	-2655077635.9284400
1977-01-01	-2958456062.7499700
1978-01-01	-3718026037.8459600
1979-01-01	-4488199907.9376300
1980-01-01	-7242752008.3670300
1981-01-01	-6882482122.2742100
1982-01-01	-5876993698.9672300
1983-01-01	-3221254077.8288100
1984-01-01	-3428348948.9427400
1985-01-01	-2427708549.2943196
1986-01-01	-48118698.9799035
1987-01-01	-387256608.3898850
1988-01-01	-317916577.7193980
1989-01-01	1354020309.6587300
1990-01-01	-1898022522.6399100
1991-01-01	-2718179513.4356200
1992-01-01	-1565851333.2595801
1993-01-01	11482071564.4429020
1994-01-01	13620604139.1294000
1995-01-01	14757061747.9102000
1996-01-01	11472731931.6757000
1997-01-01	13205401297.9820000
1998-01-01	12773331802.4361000
1999-01-01	14184077278.4600010
2000-01-01	10755148188.8219010
2001-01-01	11625177620.9977000
2002-01-01	18402677504.5766030
2003-01-01	19885191849.4927980
2004-01-01	20933619582.4159000
2005-01-01	16111341752.0658020
2006-01-01	15966694259.5354000
2007-01-01	18747738937.2055000
2008-01-01	6125233134.6621600
2009-01-01	16199158638.6388000
2010-01-01	16238358024.5176000
2011-01-01	9405070372.0807290
2012-01-01	6663189442.4245400
2013-01-01	17507939468.7478000
2014-01-01	19386470037.3230000
2015-01-01	21036071140.1196000
2016-01-01	18057584845.7248000
2017-01-01	24251044443.3425030