Quarter	Millions of US Dollars
1987-01-01	190233
1987-04-01	186389
1987-07-01	206541
1987-10-01	228947
1988-01-01	238645
1988-04-01	223461
1988-07-01	224335
1988-10-01	252443
1989-01-01	251371
1989-04-01	237313
1989-07-01	253364
1989-10-01	264873
1990-01-01	317433
1990-04-01	328192
1990-07-01	368351
1990-10-01	387096
1991-01-01	371294
1991-04-01	334028
1991-07-01	355315
1991-10-01	377646
1992-01-01	332788
1992-04-01	362652
1992-07-01	359016
1992-10-01	330892
1993-01-01	321391
1993-04-01	321242
1993-07-01	316662
1993-10-01	328605
1994-01-01	337536
1994-04-01	350487
1994-07-01	369379
1994-10-01	379825
1995-01-01	398736
1995-04-01	409896
1995-07-01	409989
1995-10-01	435178
1996-01-01	463765
1996-04-01	466465
1996-07-01	493108
1996-10-01	565394
1997-01-01	563559
1997-04-01	582706
1997-07-01	598162
1997-10-01	632966
1998-01-01	670764
1998-04-01	655422
1998-07-01	682221
1998-10-01	681632
1999-01-01	710524
1999-04-01	700006
1999-07-01	748783
1999-10-01	781805
2000-01-01	787815
2000-04-01	768916
2000-07-01	772253
2000-10-01	834719
2001-01-01	865614
2001-04-01	843189
2001-07-01	893247
2001-10-01	904381
2002-01-01	916767
2002-04-01	987880
2002-07-01	1018838
2002-10-01	1090353
2003-01-01	1162804
2003-04-01	1247018
2003-07-01	1316059
2003-10-01	1405097
2004-01-01	1546325
2004-04-01	1537408
2004-07-01	1612143
2004-10-01	1775317
2005-01-01	1816778
2005-04-01	1837966
2005-07-01	1885368
2005-10-01	1920981
2006-01-01	2064021
2006-04-01	2163707
2006-07-01	2333981
2006-10-01	2538996
2007-01-01	2663315
2007-04-01	2837842
2007-07-01	3061927
2007-10-01	3126909
2008-01-01	3220676
2008-04-01	3234101
2008-07-01	3041193
2008-10-01	2730963
2009-01-01	2712731
2009-04-01	3159980
2009-07-01	3416105
2009-10-01	3361170
2010-01-01	3172844
2010-04-01	3002613
2010-07-01	3336962
2010-10-01	3061084
2011-01-01	3226293
2011-04-01	3206514
2011-07-01	3069702
2011-10-01	2959419
2012-01-01	3054838
2012-04-01	2904785
2012-07-01	2945536
2012-10-01	3007832
2013-01-01	2819231
2013-04-01	2757481
2013-07-01	2783429
2013-10-01	2815664
2014-01-01	2916604
2014-04-01	3043809
2014-07-01	2950622
2014-10-01	2911846
2015-01-01	2844543
2015-04-01	2885609
2015-07-01	2801634
2015-10-01	2753281
2016-01-01	2646123
2016-04-01	2596580
2016-07-01	2626106
2016-10-01	2437951
2017-01-01	2481985
2017-04-01	2578672
2017-07-01	2636697
2017-10-01	2692348
2018-01-01	2817485