Year	US Dollars, Monthly Level
1991-01-01	-341378494.262606
1992-01-01	-2748728477.867100
1993-01-01	-4419822063.427569
1994-01-01	-4274932501.173630
1995-01-01	-6205257816.508340
1996-01-01	-12678706083.949600
1997-01-01	-16570721595.275402
1998-01-01	-18369288255.086900
1999-01-01	-18420913957.359802
2000-01-01	-17427524378.539200
2001-01-01	-14323555633.959400
2002-01-01	-14095599147.709301
2003-01-01	-14471074616.511500
2004-01-01	-14451671992.973299
2005-01-01	-12142515751.696000
2006-01-01	-16229135766.448100
2007-01-01	-25240566772.603600
2008-01-01	-38049142371.294500
2009-01-01	-13073172475.392300
2010-01-01	-18151545564.038902
2011-01-01	-21788432703.535400
2012-01-01	-13910153460.400900
2013-01-01	-2523344513.743270
2014-01-01	-3499829910.493920
2015-01-01	2431208588.052690
2016-01-01	4452518834.911040
2017-01-01	655471074.474359