Quarter	Billions of US Dollars
1987-04-01	-0.07000
1987-10-01	-0.02500
1988-10-01	-0.05000
1991-10-01	0.07500
1992-04-01	0.05000
1992-07-01	0.09500
1992-10-01	0.13500
1993-01-01	0.29000
1993-04-01	0.01500
1993-07-01	0.31450
1993-10-01	0.50340
1994-01-01	0.23750
1994-04-01	0.05700
1994-07-01	0.47434
1994-10-01	0.23030
1995-01-01	-0.45713
1995-04-01	0.08595
1995-07-01	-0.01349
1995-10-01	-0.03723
1996-01-01	-0.41929
1996-04-01	0.12699
1996-07-01	0.12637
1996-10-01	0.28445
1997-01-01	0.07852
1997-04-01	0.22970
1997-07-01	0.36396
1997-10-01	-0.15985
1998-01-01	0.14980
1998-04-01	0.85472
1998-07-01	-0.56238
1998-10-01	-0.20915
1999-01-01	-0.04833
1999-04-01	-0.19852
1999-07-01	-0.10276
1999-10-01	0.12223
2000-01-01	0.21149
2000-04-01	-0.56208
2000-07-01	-0.04124
2000-10-01	-0.26865
2001-01-01	0.02285
2001-04-01	-0.60702
2001-07-01	-0.10881
2001-10-01	-0.12547
2002-01-01	-0.05642
2002-04-01	0.00485
2002-07-01	-0.29000
2002-10-01	-0.09278
2003-01-01	-0.12500
2003-04-01	0.00000
2003-07-01	0.00000
2003-10-01	-0.20000
2004-01-01	0.53294
2004-10-01	0.03371
2005-04-01	-0.15796
2005-10-01	0.10300
2006-01-01	0.20000
2006-04-01	0.22300
2006-07-01	-0.10000
2006-10-01	0.12000
2007-01-01	0.05000
2007-04-01	0.42500
2008-10-01	-0.20000
2009-04-01	0.00210
2010-04-01	-0.15212
2010-07-01	-0.10794
2010-10-01	-0.20000
2011-04-01	0.30000
2012-04-01	-0.27500
2013-10-01	-0.62559