Year US Dollars, Monthly Level 1971-01-01 -374532826.319050000 1972-01-01 -284494593.281613000 1973-01-01 -29858058.342153702 1974-01-01 -4684393151.346120000 1975-01-01 -3512606162.474010000 1976-01-01 -2358488799.859349700 1977-01-01 147788102.843021000 1978-01-01 -1020063488.703760000 1979-01-01 -2718540474.531650000 1980-01-01 -2929287699.286540000 1981-01-01 1259404477.684450000 1982-01-01 886753498.393073100 1983-01-01 6451098654.623890000 1984-01-01 12908421009.395600000 1985-01-01 12473580313.846200000 1986-01-01 8587854464.380060000 1987-01-01 10859647835.369800000 1988-01-01 18976800824.407400000 1989-01-01 16332427245.783901000 1990-01-01 10906182718.801000000 1991-01-01 10953461200.204601000 1992-01-01 15174103965.141000000 1993-01-01 13651704401.186000000 1994-01-01 10741394348.702600000 1995-01-01 -3631325273.845070000 1996-01-01 -5503493733.860290000 1997-01-01 -6492407248.456820000 1998-01-01 -6271478596.561171000 1999-01-01 -1133736302.396110000 2000-01-01 -1181093653.625510200 2001-01-01 2814258082.222170000 2002-01-01 12996375762.231700000 2003-01-01 24689700984.140100000 2004-01-01 32945866942.648700000 2005-01-01 45332758754.827600000 2006-01-01 46724646449.367600000 2007-01-01 40668015962.787400000 2008-01-01 23468379471.814503000 2009-01-01 25273753369.815900000 2010-01-01 19387965813.352800000 2011-01-01 28960968000.336500000 2012-01-01 18983402782.076600000 2013-01-01 2684004713.949830000 2014-01-01 -4009618413.007509700 2015-01-01 19133390520.353500000 2016-01-01 47820317520.961800000 2017-01-01 67177458261.305700000