Quarter	Millions of US Dollars
1987-01-01	78
1987-04-01	98
1987-07-01	122
1987-10-01	157
1988-01-01	179
1988-04-01	204
1988-07-01	239
1988-10-01	265
1989-01-01	291
1989-04-01	278
1989-07-01	305
1989-10-01	367
1990-01-01	431
1990-04-01	481
1990-07-01	573
1990-10-01	624
1991-01-01	715
1991-04-01	780
1991-07-01	947
1991-10-01	1010
1992-01-01	1136
1992-04-01	1260
1992-07-01	1420
1992-10-01	1142
1993-01-01	1309
1993-04-01	1241
1993-07-01	1363
1993-10-01	1331
1994-01-01	1421
1994-04-01	1495
1994-07-01	1615
1994-10-01	1654
1995-01-01	1991
1995-04-01	2104
1995-07-01	2091
1995-10-01	2068
1996-01-01	2271
1996-04-01	2354
1996-07-01	2423
1996-10-01	2545
1997-01-01	2479
1997-04-01	2593
1997-07-01	2686
1997-10-01	2769
1998-01-01	2906
1998-04-01	3010
1998-07-01	3252
1998-10-01	3357
1999-01-01	3438
1999-04-01	3481
1999-07-01	3801
1999-10-01	3866
2000-01-01	3822
2000-04-01	3888
2000-07-01	3682
2000-10-01	3813
2001-01-01	3336
2001-04-01	3120
2001-07-01	3395
2001-10-01	3524
2002-01-01	3904
2002-04-01	4889
2002-07-01	4946
2002-10-01	5413
2003-01-01	6161
2003-04-01	6248
2003-07-01	6623
2003-10-01	7351
2004-01-01	7395
2004-04-01	7873
2004-07-01	8140
2004-10-01	9943
2005-01-01	10277
2005-04-01	9895
2005-07-01	11212
2005-10-01	10996
2006-01-01	10310
2006-04-01	10112
2006-07-01	11312
2006-10-01	12017
2007-01-01	13448
2007-04-01	14873
2007-07-01	15547
2007-10-01	16898
2008-01-01	13093
2008-04-01	15207
2008-07-01	12100
2008-10-01	6951
2009-01-01	6542
2009-04-01	6393
2009-07-01	6655
2009-10-01	6750
2010-01-01	6710
2010-04-01	6726
2010-07-01	7588
2010-10-01	7581
2011-01-01	7606
2011-04-01	7790
2011-07-01	7607
2011-10-01	8406
2012-01-01	8299
2012-04-01	8443
2012-07-01	8469
2012-10-01	8151
2013-01-01	8533
2013-04-01	8665
2013-07-01	8890
2013-10-01	9329
2014-01-01	9491
2014-04-01	9436
2014-07-01	8639
2014-10-01	8186
2015-01-01	7571
2015-04-01	7899
2015-07-01	8367
2015-10-01	8285
2016-01-01	8972
2016-04-01	9101
2016-07-01	9816
2016-10-01	10030
2017-01-01	10236
2017-04-01	11507
2017-07-01	11433
2017-10-01	11518
2018-01-01	12724