Quarter	Millions of US Dollars
2007-10-01	5386
2008-01-01	11784
2008-04-01	9486
2008-07-01	6796
2008-10-01	2838
2009-01-01	922
2009-04-01	1111
2009-07-01	3573
2009-10-01	4462
2010-01-01	7391
2010-04-01	6318
2010-07-01	10785
2010-10-01	8691
2011-01-01	8818
2011-04-01	5531
2011-07-01	6178
2011-10-01	6655
2012-01-01	10617
2012-04-01	9062
2012-07-01	9746
2012-10-01	11039
2013-01-01	13233
2013-04-01	11466
2013-07-01	8350
2013-10-01	5520
2014-01-01	4002
2014-04-01	4900
2014-07-01	4808
2014-10-01	3663
2015-01-01	4200
2015-04-01	3715
2015-07-01	4375
2015-10-01	3433
2016-01-01	3732
2016-04-01	3694
2016-07-01	5638
2016-10-01	4043
2017-01-01	6062
2017-04-01	4759
2017-07-01	7589
2017-10-01	6643
2018-01-01	8335