Quarter	Millions of US Dollars
2012-04-01	200
2012-07-01	200
2012-10-01	700
2013-01-01	1200
2013-04-01	1200
2013-07-01	1200
2013-10-01	1200
2014-01-01	1500
2014-04-01	1500
2014-07-01	2500
2014-10-01	2500
2015-01-01	2500
2015-04-01	2780
2015-07-01	2780
2015-10-01	2780
2016-01-01	3380
2016-04-01	3391
2016-07-01	3391
2016-10-01	2991
2017-01-01	3491
2017-04-01	3491
2017-07-01	3491
2017-10-01	3491
2018-01-01	4021
2018-04-01	4021