Quarter	Millions of US Dollars
1997-10-01	5048125
1998-01-01	5073408
1998-04-01	4890107
1998-07-01	5162979
1998-10-01	5956269
1999-01-01	5877783
1999-04-01	5915113
1999-07-01	6833795
1999-10-01	7175347
2000-01-01	7144794
2000-04-01	7058015
2000-07-01	6817070
2000-10-01	6571769
2001-01-01	6260539
2001-04-01	6490857
2001-07-01	6756333
2001-10-01	6205935
2002-01-01	6253989
2002-04-01	7188388
2002-07-01	7061189
2002-10-01	7334522
2003-01-01	7597588
2003-04-01	7631187
2003-07-01	8190439
2003-10-01	8611405
2004-01-01	9156089
2004-04-01	8887446
2004-07-01	8862564
2004-10-01	9755802
2005-01-01	9668655
2005-04-01	9512294
2005-07-01	9251641
2005-10-01	9024516
2006-01-01	8994949
2006-04-01	9156693
2006-07-01	9007475
2006-10-01	8942402
2007-01-01	9036722
2007-04-01	8626561
2007-07-01	9274563
2007-10-01	9686775
2008-01-01	11047046
2008-04-01	10288664
2008-07-01	10302340
2008-10-01	12149057
2009-01-01	11028548
2009-04-01	11497984
2009-07-01	12377427
2009-10-01	12102169
2010-01-01	12010873
2010-04-01	13101122
2010-07-01	14062603
2010-10-01	14422695
2011-01-01	14071086
2011-04-01	14811693
2011-07-01	15732374
2011-10-01	15634414
2012-01-01	14721374
2012-04-01	15473558
2012-07-01	15955231
2012-10-01	14538619
2013-01-01	13313960
2013-04-01	12710659
2013-07-01	12976682
2013-10-01	12146985
2014-01-01	12394580
2014-04-01	12784139
2014-07-01	11822644
2014-10-01	10943999
2015-01-01	11032742
2015-04-01	10800613
2015-07-01	11012154
2015-10-01	10986747
2016-01-01	12225257
2016-04-01	13622642
2016-07-01	13677773
2016-10-01	11730771
2017-01-01	12265851
2017-04-01	12266305
2017-07-01	12223916
2017-10-01	12298430
2018-01-01	13044885