Quarter	Millions of US Dollars
2001-07-01	150
2006-07-01	-150
2010-04-01	500
2010-10-01	2500
2012-07-01	800
2012-10-01	800
2013-04-01	3100
2013-10-01	200
2014-04-01	1046
2014-07-01	9
2014-10-01	3847
2015-01-01	-338
2015-04-01	-500
2015-07-01	140
2015-10-01	-85
2016-07-01	-1576
2016-10-01	-261
2017-01-01	15
2017-04-01	2406
2017-07-01	706
2017-10-01	-398
2018-01-01	25
2018-04-01	1660