Quarter	Millions of US Dollars
2008-01-01	3578
2008-04-01	554
2008-07-01	126
2008-10-01	937
2009-01-01	2980
2009-04-01	1352
2009-07-01	-257
2009-10-01	814
2010-01-01	3190
2010-04-01	2953
2010-07-01	1709
2010-10-01	1667
2011-01-01	3346
2011-04-01	-695
2011-07-01	2677
2011-10-01	1409
2012-01-01	1962
2012-04-01	-121
2012-07-01	89
2012-10-01	288
2013-01-01	2735
2013-04-01	1690
2013-07-01	6545
2013-10-01	703
2014-01-01	5428
2014-04-01	907
2014-07-01	1821
2014-10-01	1655
2015-01-01	1908
2015-04-01	3811
2015-07-01	908
2015-10-01	-3818
2016-01-01	4832
2016-04-01	2100
2016-07-01	2801
2016-10-01	630
2017-01-01	4810
2017-04-01	238
2017-07-01	3305
2017-10-01	749
2018-01-01	4577