Quarter	Billions of US Dollars
2006-04-01	0.20580
2007-04-01	0.20573
2009-01-01	0.15490
2010-01-01	-0.16611
2010-04-01	0.18459
2011-04-01	-0.30992
2012-04-01	-0.26695
2012-07-01	0.25895
2013-01-01	0.32841
2015-04-01	0.20791