Quarter	Billions of US Dollars
1987-01-01	-1.129
1987-04-01	0.063
1987-07-01	0.055
1987-10-01	-0.526
1988-01-01	-0.880
1988-04-01	-0.310
1988-07-01	0.391
1988-10-01	-0.220
1989-01-01	0.654
1989-04-01	0.182
1989-07-01	0.946
1989-10-01	1.085
1990-01-01	0.140
1990-04-01	-0.541
1990-07-01	2.015
1990-10-01	-0.015
1991-01-01	-0.095
1991-04-01	-0.591
1991-07-01	0.953
1991-10-01	0.132
1992-01-01	-2.131
1992-04-01	-0.692
1992-07-01	1.291
1992-10-01	0.275
1993-01-01	1.211
1993-04-01	0.017
1993-07-01	2.389
1993-10-01	3.106
1994-01-01	1.741
1994-04-01	1.307
1994-07-01	0.794
1994-10-01	3.274
1995-01-01	0.501
1995-04-01	3.716
1995-07-01	2.978
1995-10-01	1.287
1996-01-01	6.418
1996-04-01	7.694
1996-07-01	5.109
1996-10-01	19.269
1997-01-01	8.945
1997-04-01	11.561
1997-07-01	17.989
1997-10-01	19.529
1998-01-01	7.906
1998-04-01	20.140
1998-07-01	10.801
1998-10-01	4.303
1999-01-01	12.343
1999-04-01	12.418
1999-07-01	17.612
1999-10-01	6.901
2000-01-01	10.008
2000-04-01	9.677
2000-07-01	14.288
2000-10-01	15.083
2001-01-01	18.557
2001-04-01	16.904
2001-07-01	14.688
2001-10-01	13.862
2002-01-01	5.162
2002-04-01	6.392
2002-07-01	5.472
2002-10-01	3.998
2003-01-01	-4.429
2003-04-01	0.254
2003-07-01	6.340
2003-10-01	9.422
2004-01-01	5.510
2004-04-01	6.343
2004-07-01	0.425
2004-10-01	5.935
2005-01-01	8.669
2005-04-01	10.605
2005-07-01	16.014
2005-10-01	41.711
2006-01-01	46.798
2006-04-01	50.353
2006-07-01	71.782
2006-10-01	120.455
2007-01-01	104.659
2007-04-01	112.084
2007-07-01	52.675
2007-10-01	23.713
2008-01-01	-6.079
2008-04-01	6.974
2008-07-01	4.671
2008-10-01	-7.262
2009-01-01	-10.353
2009-04-01	6.031
2009-07-01	6.638
2009-10-01	6.486
2010-01-01	5.393
2010-04-01	-6.211
2010-07-01	16.533
2010-10-01	13.244
2011-01-01	6.770
2011-04-01	2.534
2011-07-01	0.847
2011-10-01	9.679
2012-01-01	20.660
2012-04-01	21.580
2012-07-01	18.240
2012-10-01	32.052
2013-01-01	17.552
2013-04-01	39.108
2013-07-01	5.290
2013-10-01	29.462
2014-01-01	22.845
2014-04-01	48.583
2014-07-01	37.858
2014-10-01	33.993
2015-01-01	32.153
2015-04-01	36.851