Quarter	Millions of US Dollars
2000-01-01	19
2000-04-01	-74
2000-07-01	68
2000-10-01	27
2001-01-01	34
2001-04-01	-31
2001-07-01	51
2001-10-01	-76
2002-01-01	41
2002-04-01	12
2002-07-01	49
2002-10-01	-294
2003-01-01	112
2003-04-01	97
2003-07-01	-54
2003-10-01	-734
2004-01-01	2
2004-04-01	715
2004-07-01	62
2004-10-01	-113
2005-01-01	-39
2005-04-01	194
2005-07-01	40
2005-10-01	-102
2006-01-01	176
2006-04-01	-71
2006-07-01	91
2006-10-01	-428
2007-01-01	-19
2007-04-01	-166
2007-07-01	56
2007-10-01	-255
2008-01-01	-61
2008-04-01	227
2008-07-01	-102
2008-10-01	-172
2009-01-01	16
2009-04-01	-602
2009-07-01	205
2009-10-01	-157
2010-01-01	-96
2010-04-01	-32
2010-07-01	18
2010-10-01	105
2011-01-01	-83
2011-04-01	-210
2011-07-01	6
2011-10-01	-10
2012-01-01	206
2012-04-01	-99
2012-07-01	-258
2012-10-01	171
2013-01-01	-89
2013-04-01	344
2013-07-01	-53
2013-10-01	58
2014-01-01	480
2014-04-01	-82
2014-07-01	226
2014-10-01	26
2015-01-01	-97
2015-04-01	21
2015-07-01	261
2015-10-01	-67
2016-01-01	1361
2016-04-01	-409
2016-07-01	115
2016-10-01	366
2017-01-01	-12
2017-04-01	396
2017-07-01	-37
2017-10-01	-343
2018-01-01	623