Quarter	Millions of US Dollars
2008-01-01	19
2008-04-01	4
2008-07-01	5
2008-10-01	0
2009-01-01	0
2009-04-01	58
2009-07-01	158
2009-10-01	0
2010-01-01	29
2010-04-01	4
2010-07-01	6
2010-10-01	737
2011-01-01	5
2011-04-01	5
2011-07-01	5
2011-10-01	-21
2012-01-01	3
2012-04-01	0
2012-07-01	-54
2012-10-01	0
2013-01-01	0
2013-04-01	114
2013-07-01	413
2013-10-01	0
2014-01-01	0
2014-04-01	0
2014-07-01	0
2014-10-01	0
2015-01-01	0
2015-04-01	135
2015-07-01	0
2015-10-01	-183
2016-01-01	132
2016-04-01	0
2016-07-01	0
2016-10-01	-327
2017-01-01	284
2017-04-01	230
2017-07-01	0
2017-10-01	-80
2018-01-01	0