Quarter	Billions of US Dollars
1987-01-01	0.23299
1987-04-01	0.37600
1987-07-01	0.29760
1987-10-01	0.49230
1988-01-01	0.08990
1988-04-01	0.07319
1988-07-01	-0.05797
1988-10-01	0.04146
1989-01-01	0.03508
1989-04-01	-0.01345
1989-07-01	0.02376
1989-10-01	-0.12912
1990-01-01	0.03690
1990-07-01	-0.03305
1990-10-01	-0.18761
1991-01-01	-0.01879
1991-04-01	-0.10139
1991-07-01	0.04370
1991-10-01	-0.22896
1992-01-01	-0.11352
1992-04-01	-0.30536
1992-07-01	-0.31671
1992-10-01	-0.08937
1993-01-01	-0.14522
1993-07-01	0.09105
1993-10-01	-0.16908
1994-01-01	0.10713
1994-04-01	-0.09510
1994-07-01	-0.08737
1994-10-01	0.23245
1995-01-01	-0.27899
1995-04-01	0.13646
1995-07-01	-0.13469
1995-10-01	0.53437
1996-01-01	0.11609
1996-04-01	0.49006
1996-07-01	-0.31530
1996-10-01	0.78237
1997-01-01	0.27793
1997-04-01	0.20909
1997-07-01	-0.17839
1997-10-01	0.44839
1998-01-01	0.04779
1998-04-01	-0.22664
1998-07-01	-0.04389
1998-10-01	-0.03870
1999-01-01	-0.03797
1999-04-01	-0.38225
1999-07-01	0.08431
1999-10-01	0.23464
2000-01-01	-0.09447
2000-04-01	0.70071
2000-07-01	-0.64972
2000-10-01	0.83948
2001-01-01	0.65183
2001-04-01	0.25917
2001-07-01	-0.38238
2001-10-01	0.24572
2002-01-01	-0.31652
2002-04-01	-0.68920
2002-07-01	0.49657
2002-10-01	-0.63246
2003-01-01	0.94162
2003-04-01	-0.62009
2003-07-01	-0.19665
2003-10-01	-0.39383
2004-01-01	0.65758
2004-04-01	0.19269
2004-07-01	0.35646
2004-10-01	0.74429
2005-01-01	-0.82282
2005-04-01	-0.68025
2005-07-01	0.06102
2005-10-01	-0.94428
2006-01-01	-0.27366
2006-04-01	-0.45155
2006-07-01	-0.04000
2006-10-01	0.25308
2007-01-01	-0.06086
2007-04-01	1.30766
2007-07-01	-0.20469
2007-10-01	0.70289
2008-01-01	-0.05000
2008-04-01	0.12693
2008-07-01	0.07328
2008-10-01	-0.37761
2009-01-01	0.01554
2009-04-01	-0.09954
2009-07-01	0.00646
2009-10-01	1.80225
2010-01-01	0.04460
2010-04-01	0.01143
2010-07-01	-0.02810
2010-10-01	0.17445
2011-01-01	-0.22831
2011-04-01	-0.05659
2011-07-01	-0.00420
2011-10-01	-0.04534
2012-01-01	-0.04588
2012-04-01	-0.25838
2013-07-01	0.05563
2013-10-01	0.32464
2014-01-01	-0.63279
2014-04-01	0.57743
2014-07-01	-0.17052