Quarter	Millions of US Dollars
1999-04-01	0
1999-07-01	0
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	0
2002-01-01	0
2002-04-01	0
2002-07-01	0
2002-10-01	0
2003-01-01	0
2003-04-01	257
2003-07-01	262
2003-10-01	284
2004-01-01	275
2004-04-01	0
2004-07-01	0
2004-10-01	0
2005-01-01	0
2005-04-01	0
2005-07-01	0
2005-10-01	6
2006-01-01	6
2006-04-01	6
2006-07-01	6
2006-10-01	0
2007-01-01	0
2007-04-01	135
2007-07-01	142
2007-10-01	442
2008-01-01	474
2008-04-01	315
2008-07-01	286
2008-10-01	0
2009-01-01	0
2009-04-01	0
2009-07-01	0
2009-10-01	0
2010-01-01	0
2010-04-01	245
2010-07-01	273
2010-10-01	267
2011-01-01	284
2011-04-01	0
2011-07-01	0
2011-10-01	0
2012-01-01	0
2012-04-01	0
2012-07-01	0
2012-10-01	0
2013-01-01	0
2013-04-01	523
2013-07-01	540
2013-10-01	552
2014-01-01	552
2014-04-01	0
2014-07-01	0
2014-10-01	0
2015-01-01	0
2015-04-01	0
2015-07-01	0
2015-10-01	0
2016-01-01	1000
2016-04-01	1000
2016-07-01	1000
2016-10-01	1000
2017-01-01	428
2017-04-01	456
2017-07-01	472
2017-10-01	480
2018-01-01	0
2018-04-01	0