Quarter	Millions of US Dollars
1986-04-01	100
1988-01-01	75
1988-07-01	268
1989-01-01	456
1989-07-01	441
1990-01-01	291
1993-04-01	-100
1994-01-01	-94
1994-07-01	-50
1995-01-01	-338
1995-07-01	-448
1995-10-01	33
1996-01-01	-5
1996-04-01	21
1996-07-01	-993
1996-10-01	985
1997-01-01	1164
1997-04-01	2835
1997-07-01	150
1997-10-01	636
1998-01-01	996
1998-04-01	4940
1998-07-01	6393
1998-10-01	-100
1999-04-01	-100
1999-07-01	-1
1999-10-01	-219
2000-04-01	-281
2000-07-01	20519
2001-01-01	-150
2001-04-01	-459
2001-10-01	-176
2002-01-01	525
2002-04-01	800
2002-10-01	1655
2003-01-01	2040
2003-04-01	-1215
2003-07-01	0
2003-10-01	1055
2004-01-01	-698
2004-04-01	1193
2004-07-01	750
2004-10-01	246
2005-01-01	762
2005-04-01	-50
2005-07-01	-2317
2005-10-01	35
2006-01-01	-31
2006-04-01	939
2006-07-01	1174
2006-10-01	5665
2007-01-01	3929
2007-04-01	2059
2007-07-01	240
2007-10-01	-491
2008-01-01	-466
2008-04-01	2630
2008-07-01	3753
2008-10-01	-221
2009-01-01	-1516
2009-04-01	1663
2009-07-01	-1516
2009-10-01	-927
2010-01-01	-3171
2010-04-01	6275
2010-07-01	521
2010-10-01	1824
2011-01-01	4286
2011-04-01	2545
2011-07-01	-1730
2011-10-01	-1061
2012-01-01	-795
2012-04-01	15897
2012-07-01	11455
2012-10-01	10253
2013-01-01	4990
2013-04-01	7077
2013-07-01	4143
2013-10-01	4092
2014-01-01	-11696
2014-04-01	258
2014-07-01	1185
2014-10-01	304
2015-01-01	-882
2015-04-01	-2173
2015-07-01	-3438
2015-10-01	15
2016-01-01	-1555
2016-04-01	1100
2016-07-01	135
2016-10-01	1346
2017-01-01	-2771
2017-04-01	-648
2017-07-01	6084
2017-10-01	-2184
2018-01-01	91
2018-04-01	-3986