Quarter	Millions of US Dollars
1997-10-01	1230376
1998-01-01	1224571
1998-04-01	1134023
1998-07-01	1200733
1998-10-01	1365982
1999-01-01	1363089
1999-04-01	1320119
1999-07-01	1523686
1999-10-01	1588006
2000-01-01	1550441
2000-04-01	1457342
2000-07-01	1408858
2000-10-01	1338586
2001-01-01	1255412
2001-04-01	1344297
2001-07-01	1490605
2001-10-01	1419674
2002-01-01	1468971
2002-04-01	1677591
2002-07-01	1692311
2002-10-01	1810633
2003-01-01	1916661
2003-04-01	1919778
2003-07-01	2089780
2003-10-01	2187159
2004-01-01	2321847
2004-04-01	2219982
2004-07-01	2279503
2004-10-01	2547711
2005-01-01	2572233
2005-04-01	2508371
2005-07-01	2479990
2005-10-01	2659356
2006-01-01	2694482
2006-04-01	2701719
2006-07-01	2652744
2006-10-01	2613807
2007-01-01	2646736
2007-04-01	2527589
2007-07-01	2688539
2007-10-01	2774817
2008-01-01	3113769
2008-04-01	2857968
2008-07-01	2842962
2008-10-01	3280328
2009-01-01	2949737
2009-04-01	2965359
2009-07-01	3192922
2009-10-01	3071618
2010-01-01	3017667
2010-04-01	3216368
2010-07-01	3425322
2010-10-01	3451267
2011-01-01	3305781
2011-04-01	3377672
2011-07-01	3491093
2011-10-01	3467396
2012-01-01	3266424
2012-04-01	3364739
2012-07-01	3414666
2012-10-01	3158006
2013-01-01	2862243
2013-04-01	2679954
2013-07-01	2701563
2013-10-01	2512352
2014-01-01	2554011
2014-04-01	2574907
2014-07-01	2386123
2014-10-01	2217949
2015-01-01	2224934
2015-04-01	2150917
2015-07-01	2192934
2015-10-01	2212061
2016-01-01	2538771
2016-04-01	2674329
2016-07-01	2674861
2016-10-01	2343842
2017-01-01	2481683
2017-04-01	2459581
2017-07-01	2451342
2017-10-01	2475199
2018-01-01	2634245