Quarter	Millions of US Dollars
1990-07-01	111
1993-07-01	-111
1994-04-01	20
1994-07-01	0
1994-10-01	5840
1995-01-01	-20
1995-07-01	250
1996-04-01	100
1996-07-01	154
1996-10-01	40
1997-04-01	330
1997-07-01	653
1997-10-01	563
1998-01-01	1
1998-04-01	1
1998-07-01	101
1998-10-01	507
1999-01-01	-5
1999-04-01	156
1999-07-01	463
1999-10-01	924
2000-01-01	1131
2000-04-01	-412
2000-07-01	-248
2000-10-01	-942
2001-01-01	1540
2001-04-01	-139
2001-07-01	-112
2001-10-01	1046
2002-01-01	461
2002-04-01	-31
2002-07-01	1377
2002-10-01	-701
2003-01-01	1611
2003-04-01	-202
2003-07-01	1322
2003-10-01	1301
2004-01-01	2757
2004-04-01	1267
2004-07-01	-172
2004-10-01	-512
2005-01-01	4591
2005-04-01	6413
2005-07-01	-901
2005-10-01	2119
2006-01-01	3609
2006-04-01	184
2006-07-01	-635
2006-10-01	567
2007-01-01	-400
2007-04-01	1706
2007-07-01	-298
2007-10-01	-968
2008-01-01	-777
2008-04-01	3494
2008-07-01	-210
2008-10-01	-900
2009-01-01	1931
2009-04-01	1700
2009-07-01	3421
2009-10-01	3029
2010-01-01	5488
2010-04-01	-480
2010-07-01	2958
2010-10-01	728
2011-01-01	605
2011-04-01	2816
2011-07-01	601
2011-10-01	2247
2012-01-01	4427
2012-04-01	1404
2012-07-01	3209
2012-10-01	5237
2013-01-01	-2905
2013-04-01	-426
2013-07-01	964
2013-10-01	1609
2014-01-01	340
2014-04-01	-2631
2014-07-01	1250
2014-10-01	-287
2015-04-01	177
2015-07-01	209
2015-10-01	-1832
2016-01-01	-1535
2016-04-01	3717
2016-07-01	-1562
2016-10-01	2623
2017-01-01	-451
2017-04-01	-479
2017-07-01	2030
2017-10-01	4624
2018-01-01	1844
2018-04-01	-2336