Quarter	Millions of US Dollars
1996-10-01	1200
1999-04-01	1000
2000-04-01	1400
2002-01-01	-73
2002-07-01	-36
2003-01-01	-36
2003-10-01	700
2004-01-01	592
2004-07-01	-36
2005-01-01	-36
2005-07-01	2214
2006-01-01	-36
2006-04-01	1150
2006-07-01	1514
2006-10-01	1490
2007-07-01	300
2008-01-01	138
2008-04-01	163
2009-04-01	3500
2009-07-01	1485
2009-10-01	8600
2010-01-01	-80
2010-04-01	550
2010-07-01	4070
2010-10-01	4186
2011-01-01	-80
2011-04-01	-650
2011-07-01	97
2011-10-01	4500
2012-01-01	420
2012-04-01	564
2012-07-01	4319
2012-10-01	6270
2013-01-01	3121
2013-04-01	2477
2013-07-01	-181
2013-10-01	2987
2014-01-01	608
2014-04-01	-2365
2014-07-01	644
2014-10-01	501
2015-01-01	-1842
2015-04-01	1516
2015-07-01	-927
2015-10-01	-1590
2016-01-01	3379
2016-04-01	13922
2016-07-01	3248
2016-10-01	-2351
2017-01-01	-308
2017-04-01	830
2017-07-01	-6992
2017-10-01	-1901
2018-01-01	1298
2018-04-01	12663