Quarter	Millions of US Dollars
1985-01-01	19
1986-07-01	26
1988-04-01	40
1990-01-01	-34
1991-07-01	-32
1994-04-01	14
1994-07-01	0
1994-10-01	30
1995-10-01	124
1996-01-01	199
1996-04-01	-114
1996-07-01	19
1996-10-01	-79
1997-01-01	-123
1997-04-01	130
1997-07-01	-109
1997-10-01	-44
1998-04-01	-37
1999-10-01	-30
2000-04-01	100
2001-10-01	150
2004-07-01	2
2004-10-01	18
2005-01-01	216
2005-04-01	2
2005-07-01	-11
2005-10-01	115
2006-01-01	-1
2006-04-01	150
2006-07-01	25
2006-10-01	50
2007-04-01	10
2007-07-01	27
2007-10-01	54
2008-01-01	349
2008-04-01	0
2008-07-01	5
2008-10-01	-15
2009-01-01	-26
2009-04-01	-25
2009-07-01	5
2009-10-01	438
2010-01-01	-208
2010-04-01	85
2010-07-01	200
2010-10-01	-10
2011-07-01	-141
2011-10-01	-5
2012-04-01	12
2012-07-01	250
2012-10-01	-8
2013-04-01	472
2013-07-01	7
2013-10-01	22
2014-01-01	1250
2014-04-01	-450
2014-10-01	-190
2015-07-01	361
2015-10-01	-5
2016-01-01	-4
2016-04-01	-150
2016-07-01	-86
2016-10-01	-2
2017-04-01	280
2017-07-01	-1262
2017-10-01	-16