Quarter	Millions of US Dollars
2002-04-01	147267
2002-07-01	149396
2002-10-01	162791
2003-01-01	166358
2003-04-01	178270
2003-07-01	191539
2003-10-01	185221
2004-01-01	201036
2004-04-01	208105
2004-07-01	210335
2004-10-01	255693
2005-01-01	275963
2005-04-01	272208
2005-07-01	270230
2005-10-01	284830
2006-01-01	306998
2006-04-01	330925
2006-07-01	347806
2006-10-01	357297
2007-01-01	372622
2007-04-01	392141
2007-07-01	402576
2007-10-01	403049
2008-01-01	384327
2008-04-01	376367
2008-07-01	332058
2008-10-01	299552
2009-01-01	295318
2009-04-01	334596
2009-07-01	356407
2009-10-01	358814
2010-01-01	369007
2010-04-01	345784
2010-07-01	360407
2010-10-01	359708
2011-01-01	366610
2011-04-01	376557
2011-07-01	343414
2011-10-01	346997
2012-01-01	355666
2012-04-01	345528
2012-07-01	352017
2012-10-01	371946
2013-01-01	361451
2013-04-01	355295
2013-07-01	382814
2013-10-01	395773
2014-01-01	397193
2014-04-01	420192
2014-07-01	411662
2014-10-01	451565
2015-01-01	453922
2015-04-01	456499
2015-07-01	434131
2015-10-01	437909
2016-01-01	458626
2016-04-01	455126
2016-07-01	480002
2016-10-01	431128
2017-01-01	467942
2017-04-01	467737
2017-07-01	471494
2017-10-01	520638
2018-01-01	530186