Quarter	Millions of US Dollars
1987-04-01	1468
1987-07-01	1330
1987-10-01	2295
1988-01-01	2120
1988-04-01	3061
1988-07-01	2943
1988-10-01	7003
1989-01-01	7502
1989-04-01	4595
1989-07-01	3793
1989-10-01	1299
1990-01-01	0
1990-04-01	0
1990-07-01	0
1990-10-01	663
1991-01-01	2911
1991-04-01	1475
1991-07-01	6723
1991-10-01	4505
1992-01-01	5449
1992-04-01	12535
1992-07-01	3930
1992-10-01	3149
1993-01-01	2413
1993-04-01	0
1993-07-01	371
1993-10-01	1127
1994-01-01	1519
1994-04-01	932
1994-07-01	382
1994-10-01	571
1995-01-01	577
1995-04-01	0
1995-07-01	0
1995-10-01	183
1996-01-01	1233
1996-04-01	701
1996-07-01	1637
1996-10-01	545
1997-01-01	544
1997-04-01	539
1997-07-01	779
1997-10-01	610
1998-01-01	483
1998-04-01	0
1998-07-01	0
1998-10-01	1704
1999-01-01	3017
1999-04-01	3251
1999-07-01	3776
1999-10-01	4782
2000-01-01	3937
2000-04-01	3250
2000-07-01	639
2000-10-01	1359
2001-01-01	609
2001-04-01	1016
2001-07-01	434
2001-10-01	1426
2002-01-01	1429
2002-04-01	2980
2002-07-01	4295
2002-10-01	5179
2003-01-01	5180
2003-04-01	3178
2003-07-01	1777
2003-10-01	1765
2004-01-01	1817
2004-04-01	1628
2004-07-01	2060
2004-10-01	4115
2005-01-01	4154
2005-04-01	3795
2005-07-01	1506
2005-10-01	1370
2006-01-01	770
2006-04-01	1390
2006-07-01	1359
2006-10-01	767
2007-01-01	2568
2007-04-01	1832
2007-07-01	918
2007-10-01	863
2008-01-01	4707
2008-04-01	6029
2008-07-01	2951
2008-10-01	3253
2009-01-01	7721
2009-04-01	7469
2009-07-01	5441
2009-10-01	6724
2010-01-01	6916
2010-04-01	5580
2010-07-01	5427
2010-10-01	8233
2011-01-01	7820
2011-04-01	6207
2011-07-01	4518
2011-10-01	5950
2012-01-01	6107
2012-04-01	4362
2012-07-01	3925
2012-10-01	6713
2013-01-01	8702
2013-04-01	5808
2013-07-01	7587
2013-10-01	7195
2014-01-01	8038
2014-04-01	6194
2014-07-01	4435
2014-10-01	4106
2015-01-01	5559
2015-04-01	2548
2015-07-01	3306
2015-10-01	2738
2016-01-01	6763
2016-04-01	3335
2016-07-01	2871
2016-10-01	2774
2017-01-01	7567
2017-04-01	3621
2017-07-01	2636
2017-10-01	843
2018-01-01	5488