Quarter	Millions of US Dollars
1995-04-01	0
1995-07-01	0
1995-10-01	1
1996-01-01	0
1996-04-01	1
1996-07-01	0
1996-10-01	3
1997-01-01	1
1997-04-01	-1
1997-07-01	0
1997-10-01	-2
1998-01-01	1
1998-04-01	2
1998-07-01	0
1998-10-01	-1
1999-01-01	1
1999-04-01	15581
1999-07-01	1
1999-10-01	21558
2000-01-01	314
2000-04-01	10859
2000-07-01	3049
2000-10-01	2009
2001-01-01	141
2001-04-01	205
2001-07-01	274
2001-10-01	-998
2002-01-01	281
2002-04-01	200
2002-07-01	-155
2002-10-01	-443
2003-01-01	-636
2003-04-01	-401
2003-07-01	-269
2003-10-01	912
2004-01-01	-246
2004-04-01	-303
2004-07-01	1030
2004-10-01	468
2005-01-01	946
2005-04-01	-336
2005-07-01	132
2005-10-01	-664
2006-01-01	-18
2006-04-01	832
2006-07-01	1891
2006-10-01	-661
2007-01-01	2203
2007-04-01	1772
2007-07-01	1925
2007-10-01	566
2008-01-01	57546
2008-04-01	-8568
2008-07-01	-8702
2008-10-01	10708
2009-01-01	9901
2009-04-01	1306
2009-07-01	-908
2009-10-01	10240
2010-01-01	11009
2010-04-01	-3043
2010-07-01	-198
2010-10-01	-10659
2011-01-01	11503
2011-04-01	-7139
2011-07-01	-7223
2011-10-01	-4611
2012-01-01	-7482
2012-04-01	4456
2012-07-01	-5970
2012-10-01	9976
2013-01-01	6045
2013-04-01	2996
2013-07-01	4040
2013-10-01	7032
2014-01-01	8171
2014-04-01	8262
2014-07-01	5711
2014-10-01	9249
2015-01-01	8878
2015-04-01	-705
2015-07-01	12845
2015-10-01	1335
2016-01-01	16907
2016-04-01	7317
2016-07-01	11921
2016-10-01	-227
2017-01-01	14240
2017-04-01	5449
2017-07-01	6806
2017-10-01	8969
2018-01-01	11130