Year	US Dollars, Monthly Level
1990-01-01	23583628321.764
1991-01-01	20488000000.000
1992-01-01	21743000000.000
1993-01-01	22330000000.000
1994-01-01	26842000000.000
1995-01-01	34709000000.000
1996-01-01	37946000000.000
1997-01-01	41436000000.000
1998-01-01	42975000000.000
1999-01-01	46968000000.000
2000-01-01	51561000000.000
2001-01-01	50401000000.000
2002-01-01	56532000000.000
2003-01-01	72569000000.000
2004-01-01	99781000000.000
2005-01-01	142870000000.000
2006-01-01	178410000000.000
2007-01-01	229369900000.000
2008-01-01	321031800000.000
2009-01-01	257202200000.000
2010-01-01	350232800000.000
2011-01-01	464461808040.000
2012-01-01	489693916210.000
2013-01-01	465401805970.000
2014-01-01	462920273230.000
2015-01-01	393831433510.000
2016-01-01	361496571410.000
2017-01-01	449795403360.000
