Quarter	Millions of US Dollars
1997-10-01	2609962
1998-01-01	2623202
1998-04-01	2561767
1998-07-01	2767369
1998-10-01	3247202
1999-01-01	3289164
1999-04-01	3270719
1999-07-01	3851292
1999-10-01	4056116
2000-01-01	4088700
2000-04-01	4066726
2000-07-01	4007160
2000-10-01	3914243
2001-01-01	3730028
2001-04-01	3814690
2001-07-01	3968259
2001-10-01	3642398
2002-01-01	3637353
2002-04-01	4157258
2002-07-01	4136838
2002-10-01	4284562
2003-01-01	4355196
2003-04-01	4329269
2003-07-01	4651876
2003-10-01	4897062
2004-01-01	5124849
2004-04-01	4920204
2004-07-01	4994766
2004-10-01	5497266
2005-01-01	5390576
2005-04-01	5333850
2005-07-01	5210316
2005-10-01	5062105
2006-01-01	4989329
2006-04-01	5082046
2006-07-01	5061771
2006-10-01	5020507
2007-01-01	5045840
2007-04-01	4738526
2007-07-01	5168839
2007-10-01	5399665
2008-01-01	6198224
2008-04-01	5793267
2008-07-01	5813617
2008-10-01	6921368
2009-01-01	6239768
2009-04-01	6410447
2009-07-01	6908726
2009-10-01	6753674
2010-01-01	6732405
2010-04-01	7364902
2010-07-01	8050407
2010-10-01	8324813
2011-01-01	8211390
2011-04-01	8633328
2011-07-01	9212893
2011-10-01	9245833
2012-01-01	8798992
2012-04-01	9246496
2012-07-01	9606884
2012-10-01	8652869
2013-01-01	8150160
2013-04-01	7755622
2013-07-01	8060530
2013-10-01	7610666
2014-01-01	7824642
2014-04-01	8116708
2014-07-01	7581139
2014-10-01	7165088
2015-01-01	7139882
2015-04-01	7045470
2015-07-01	7280636
2015-10-01	7378475
2016-01-01	8239945
2016-04-01	9335552
2016-07-01	9360532
2016-10-01	8002748
2017-01-01	8375663
2017-04-01	8423888
2017-07-01	8467685
2017-10-01	8545455
2018-01-01	9088515