Quarter	Billions of US Dollars
1987-01-01	0.8040
1987-04-01	0.8770
1987-07-01	0.5980
1987-10-01	0.5780
1988-01-01	0.6480
1988-04-01	0.6750
1988-07-01	0.6760
1988-10-01	0.6580
1989-01-01	0.7230
1989-04-01	0.8710
1989-07-01	0.7320
1989-10-01	0.5600
1990-01-01	0.8020
1990-04-01	0.7360
1990-07-01	0.7850
1990-10-01	0.4970
1991-01-01	0.5910
1991-04-01	0.5840
1991-07-01	0.5010
1991-10-01	0.3480
1992-01-01	0.3860
1992-04-01	0.4290
1992-07-01	0.3690
1992-10-01	0.1870
1993-01-01	0.5620
1993-04-01	0.3480
1993-07-01	0.3020
1993-10-01	0.3035
1994-01-01	0.3662
1994-04-01	0.3420
1994-07-01	0.2664
1994-10-01	0.2427
1995-01-01	0.2857
1995-04-01	0.8305
1995-07-01	1.7360
1995-10-01	2.4178
1996-01-01	2.4355
1996-04-01	2.6909
1996-07-01	4.3868
1996-10-01	5.7700
1997-01-01	5.1887
1997-04-01	4.6501
1997-07-01	3.7215
1997-10-01	1.8064
1998-01-01	1.4531
1998-04-01	1.6415
1998-07-01	1.1725
1998-10-01	1.0755
1999-01-01	1.1740
1999-04-01	0.8501
1999-07-01	0.7453
1999-10-01	0.9082
2000-01-01	1.1248
2000-04-01	1.4831
2000-07-01	1.8080
2000-10-01	1.8410
2001-01-01	1.2497
2001-04-01	1.4207
2001-07-01	1.0377
2001-10-01	0.8295
2002-01-01	0.6047
2002-04-01	1.0167
2002-07-01	2.3522
2002-10-01	2.1256
2003-01-01	2.3188
2003-04-01	1.8859
2003-07-01	1.6302
2003-10-01	1.9779
2004-01-01	1.8401
2004-04-01	1.4072
2004-07-01	1.1607
2004-10-01	1.6587
2005-01-01	1.8088
2005-04-01	2.3764
2005-07-01	1.8437
2005-10-01	1.9582
2006-01-01	2.4976
2006-04-01	3.2840
2006-07-01	4.4450
2006-10-01	4.1348
2007-01-01	4.9268
2007-04-01	5.3880
2007-07-01	6.6244
2007-10-01	6.7555
2008-01-01	7.3821
2008-04-01	8.8928
2008-07-01	8.5647
2008-10-01	3.3171
2009-01-01	3.8984
2009-04-01	6.1875
2009-07-01	6.7423
2009-10-01	6.7189
2010-01-01	6.3012
2010-04-01	5.9836
2010-07-01	5.8528
2010-10-01	4.1415
2011-01-01	4.4087
2011-04-01	4.6460
2011-07-01	5.2891
2011-10-01	6.4497
2012-01-01	6.6612
2012-04-01	7.0585
2012-07-01	7.4370
2012-10-01	6.0668
2013-01-01	6.0372
2013-04-01	6.3118
2013-07-01	7.4840
2013-10-01	8.2953
2014-01-01	9.0383
2014-04-01	8.3180
2014-07-01	7.0854
2014-10-01	8.0192
2015-01-01	8.9829
2015-04-01	10.4445