Quarter	Millions of US Dollars
1996-10-01	0
1997-01-01	0
1997-04-01	0
1997-07-01	0
1997-10-01	0
1998-01-01	0
1998-04-01	0
1998-07-01	0
1998-10-01	200
1999-01-01	200
1999-04-01	200
1999-07-01	200
1999-10-01	0
2000-01-01	0
2000-04-01	0
2000-07-01	0
2000-10-01	0
2001-01-01	0
2001-04-01	0
2001-07-01	0
2001-10-01	350
2002-01-01	350
2002-04-01	350
2002-07-01	350
2002-10-01	0
2003-01-01	0
2003-04-01	0
2003-07-01	0
2003-10-01	300
2004-01-01	300
2004-04-01	300
2004-07-01	300
2004-10-01	0
2005-01-01	0
2005-04-01	0
2005-07-01	150
2005-10-01	150
2006-01-01	150
2006-04-01	800
2006-07-01	650
2006-10-01	950
2007-01-01	1196
2007-04-01	846
2007-07-01	846
2007-10-01	696
2008-01-01	575
2008-04-01	275
2008-07-01	275
2008-10-01	525
2009-01-01	400
2009-04-01	400
2009-07-01	400
2009-10-01	200
2010-01-01	200
2010-04-01	340
2010-07-01	1022
2010-10-01	825
2011-01-01	870
2011-04-01	1013
2011-07-01	287
2011-10-01	244
2012-01-01	293
2012-04-01	50
2012-07-01	50
2012-10-01	150
2013-01-01	150
2013-04-01	200
2013-07-01	1200
2013-10-01	1100
2014-01-01	1100
2014-04-01	1500
2014-07-01	1250
2014-10-01	3304
2015-01-01	3385
2015-04-01	2709
2015-07-01	2159
2015-10-01	1397
2016-01-01	1328
2016-04-01	1245
2016-07-01	1105
2016-10-01	803
2017-01-01	904
2017-04-01	1842
2017-07-01	1694
2017-10-01	1274
2018-01-01	1174
2018-04-01	1500