Quarter	Millions of US Dollars
1995-04-01	-75
1995-07-01	-219
1995-10-01	587
1996-01-01	-442
1996-04-01	705
1996-07-01	-346
1996-10-01	2919
1997-01-01	1010
1997-04-01	-1497
1997-07-01	-142
1997-10-01	-2114
1998-01-01	1188
1998-04-01	2086
1998-07-01	67
1998-10-01	-743
1999-01-01	736
1999-04-01	2208
1999-07-01	1110
1999-10-01	-1446
2000-01-01	3335
2000-04-01	-1015
2000-07-01	-139
2000-10-01	-1869
2001-01-01	851
2001-04-01	771
2001-07-01	-672
2001-10-01	-1474
2002-01-01	4524
2002-04-01	274
2002-07-01	-534
2002-10-01	-2248
2003-01-01	4751
2003-04-01	429
2003-07-01	1159
2003-10-01	-3110
2004-01-01	3895
2004-04-01	-2512
2004-07-01	-5885
2004-10-01	4409
2005-01-01	2512
2005-04-01	-2758
2005-07-01	-5750
2005-10-01	3370
2006-01-01	6527
2006-04-01	3658
2006-07-01	1385
2006-10-01	3257
2007-01-01	3717
2007-04-01	1586
2007-07-01	891
2007-10-01	-1940
2008-01-01	23059
2008-04-01	-10630
2008-07-01	-10226
2008-10-01	11038
2009-01-01	8779
2009-04-01	374
2009-07-01	-2385
2009-10-01	8840
2010-01-01	9431
2010-04-01	-6041
2010-07-01	-3506
2010-10-01	-10272
2011-01-01	7697
2011-04-01	-8897
2011-07-01	-8025
2011-10-01	-7690
2012-01-01	-12037
2012-04-01	546
2012-07-01	-2539
2012-10-01	3102
2013-01-01	1695
2013-04-01	-501
2013-07-01	-1143
2013-10-01	2382
2014-01-01	1293
2014-04-01	2264
2014-07-01	-272
2014-10-01	7799
2015-01-01	1720
2015-04-01	-5319
2015-07-01	4326
2015-10-01	-2784
2016-01-01	8510
2016-04-01	1310
2016-07-01	3983
2016-10-01	-1623
2017-01-01	5430
2017-04-01	706
2017-07-01	-245
2017-10-01	3303
2018-01-01	4217