Quarter	Millions of US Dollars
1995-10-01	62
1998-01-01	200
1998-04-01	864
1998-07-01	-88
1999-04-01	412
1999-07-01	102
2000-04-01	484
2000-07-01	101
2000-10-01	-59
2001-04-01	98
2002-10-01	-256
2003-04-01	-306
2003-07-01	-93
2003-10-01	287
2004-01-01	0
2004-04-01	597
2005-04-01	-944
2006-01-01	1202
2007-04-01	1348
2009-04-01	2724
2010-04-01	1414
2011-01-01	1703
2011-04-01	1445
2012-04-01	3550
2013-04-01	2220
2014-01-01	562
2014-04-01	-1371
2014-10-01	-721
2015-01-01	-1601
2016-01-01	-1377
2016-04-01	-239
2017-04-01	-1102
2018-04-01	-368