Year	US Dollars, Monthly Level
1999-01-01	10483455777.941700
2000-01-01	10205366465.679998
2001-01-01	10328279759.679100
2002-01-01	11003576805.487900
2003-01-01	13075685550.736900
2004-01-01	16160980743.224400
2005-01-01	19149971228.527200
2006-01-01	23377742937.245600
2007-01-01	30488345857.071400
2008-01-01	34046298786.092003
2009-01-01	25938117867.095100
2010-01-01	28895528342.918500
2011-01-01	34579940562.008095
2012-01-01	32398976571.705902
2013-01-01	34306442183.976000
2014-01-01	36049748692.975100
2015-01-01	31742279476.385600
2016-01-01	32871076180.936398
2017-01-01	38668660245.949800