Quarter	Millions of US Dollars
2004-01-01	9583
2004-04-01	10367
2004-07-01	11025
2004-10-01	41231
2005-01-01	43227
2005-04-01	45633
2005-07-01	49124
2005-10-01	54109
2006-01-01	61537
2006-04-01	64910
2006-07-01	70639
2006-10-01	79877
2007-01-01	86345
2007-04-01	96156
2007-07-01	103075
2007-10-01	108098
2008-01-01	123936
2008-04-01	129866
2008-07-01	125897
2008-10-01	110516
2009-01-01	97973
2009-04-01	113428
2009-07-01	133486
2009-10-01	148390
2010-01-01	153365
2010-04-01	146001
2010-07-01	164644
2010-10-01	180023
2011-01-01	209149
2011-04-01	223211
2011-07-01	194494
2011-10-01	206978
2012-01-01	236856
2012-04-01	216002
2012-07-01	231494
2012-10-01	253431
2013-01-01	254813
2013-04-01	251619
2013-07-01	264354
2013-10-01	281562
2014-01-01	259867
2014-04-01	280551
2014-07-01	241694
2014-10-01	175378
2015-01-01	206339
2015-04-01	222602
2015-07-01	194967
2015-10-01	176988
2016-01-01	200606
2016-04-01	215799
2016-07-01	221518
2016-10-01	247825
2017-01-01	279207
2017-04-01	278023
2017-07-01	298352
2017-10-01	317442
2018-01-01	323072