Quarter	Millions of US Dollars
1975-07-01	25
1978-07-01	25
1980-10-01	29
1982-07-01	-25
1985-10-01	-1
1986-07-01	-25
1986-10-01	-28
1993-04-01	333
1993-10-01	100
1994-01-01	-111
1994-10-01	100
1996-01-01	750
1996-04-01	500
1996-07-01	440
1996-10-01	800
1997-10-01	650
1998-04-01	500
1998-10-01	213
1999-01-01	200
1999-04-01	700
1999-07-01	286
2000-07-01	300
2001-04-01	605
2001-07-01	356
2002-07-01	371
2002-10-01	716
2003-01-01	-72
2003-04-01	274
2003-07-01	860
2003-10-01	-41
2004-01-01	243
2004-07-01	-253
2004-10-01	500
2005-01-01	-82
2005-04-01	150
2005-07-01	305
2006-01-01	-657
2006-04-01	50
2006-07-01	-400
2006-10-01	200
2007-01-01	-16
2007-07-01	-9
2007-10-01	-250
2008-01-01	-9
2008-04-01	-20
2008-07-01	-8
2009-01-01	591
2009-04-01	-557
2009-07-01	651
2009-10-01	1051
2010-01-01	490
2010-04-01	250
2010-07-01	693
2010-10-01	1700
2011-01-01	1645
2011-04-01	226
2011-07-01	-112
2011-10-01	1631
2012-01-01	300
2012-04-01	503
2012-07-01	1482
2012-10-01	859
2013-01-01	900
2013-04-01	1050
2013-07-01	1045
2013-10-01	3161
2014-01-01	-400
2014-04-01	700
2014-07-01	4596
2014-10-01	3013
2015-01-01	1000
2015-04-01	2642
2015-07-01	2342
2015-10-01	-300
2016-04-01	-200
2016-07-01	1050
2016-10-01	250
2017-01-01	500
2017-04-01	2116
2017-07-01	6448
2017-10-01	205
2018-04-01	1214