Quarter	Billions of US Dollars
2012-04-01	0.20
2012-07-01	0.20
2012-10-01	0.70
2013-01-01	1.20
2013-04-01	1.20
2013-07-01	1.20
2013-10-01	1.20
2014-01-01	1.50
2014-04-01	1.50
2014-07-01	2.50
2014-10-01	2.50
2015-01-01	2.50
2015-04-01	2.78