Quarter	Millions of US Dollars
2008-01-01	5984
2008-04-01	-493
2008-07-01	-2918
2008-10-01	-2544
2009-01-01	-332
2009-04-01	-2302
2009-07-01	1023
2009-10-01	1187
2010-01-01	2779
2010-04-01	-843
2010-07-01	4849
2010-10-01	-816
2011-01-01	173
2011-04-01	-2904
2011-07-01	150
2011-10-01	229
2012-01-01	4506
2012-04-01	-1269
2012-07-01	874
2012-10-01	2002
2013-01-01	3315
2013-04-01	28
2013-07-01	-2735
2013-10-01	-2746
2014-01-01	-1381
2014-04-01	1079
2014-07-01	1053
2014-10-01	997
2015-01-01	2170
2015-04-01	-53
2015-07-01	1310
2015-10-01	-549
2016-01-01	757
2016-04-01	1336
2016-07-01	4425
2016-10-01	1150
2017-01-01	4519
2017-04-01	245
2017-07-01	7003
2017-10-01	-1085
2018-01-01	710