Quarter	Billions of US Dollars
1987-07-01	0.03800
1987-10-01	0.02200
1988-01-01	0.09400
1988-04-01	0.06500
1988-07-01	0.05700
1989-10-01	0.07600
1990-01-01	0.08600
1990-04-01	0.03500
1990-07-01	0.36800
1990-10-01	0.30100
1991-01-01	0.61100
1991-04-01	0.73200
1991-07-01	0.88400
1991-10-01	0.93900
1992-01-01	0.94100
1992-04-01	1.00500
1992-07-01	0.53500
1992-10-01	0.27000
1993-10-01	0.07330
1994-01-01	0.22060
1994-04-01	0.56020
1994-07-01	0.40490
1994-10-01	0.71525
1995-01-01	0.27020
1995-04-01	0.29169
1995-07-01	0.47776
1995-10-01	0.57626
1996-01-01	0.67028
1996-04-01	0.49221
1996-07-01	0.31193
1996-10-01	0.39510
1997-01-01	0.24821
1997-04-01	0.33743
1997-07-01	0.40564
1997-10-01	0.25903
1998-01-01	0.28477
1998-04-01	0.31980
1998-07-01	0.29972
1998-10-01	0.28917
1999-01-01	0.21220
1999-04-01	0.18575
1999-07-01	0.15657
1999-10-01	0.14581
2000-01-01	0.16629
2000-04-01	0.18809
2000-07-01	0.20266
2000-10-01	0.17546
2001-01-01	0.17203
2001-04-01	0.23061
2001-07-01	0.23886
2001-10-01	0.20108
2002-01-01	0.15414
2002-04-01	0.08379
2002-07-01	0.06699
2002-10-01	0.07440
2003-01-01	0.07707
2003-04-01	0.07750
2003-07-01	0.07146
2003-10-01	0.09630
2004-01-01	0.09863
2004-04-01	0.09851
2004-07-01	0.07547
2004-10-01	0.06522
2005-01-01	0.05016
2005-04-01	0.05653
2005-07-01	0.05633
2005-10-01	0.03998
2006-01-01	0.03321
2006-04-01	0.03630
2006-07-01	0.03965
2006-10-01	0.03662
2007-01-01	0.03484
2007-04-01	0.02606
2007-07-01	0.02976
2007-10-01	0.03261
2008-01-01	0.03230
2008-04-01	0.02603
2008-07-01	0.02352
2008-10-01	0.02648
2009-01-01	0.02238
2009-04-01	0.02437
2009-07-01	0.02289
2009-10-01	0.02030
2010-01-01	0.01507
2010-04-01	0.01267
2010-07-01	0.01410
2010-10-01	0.01380
2011-01-01	0.01467
2011-04-01	0.01493
2011-07-01	0.01395
2011-10-01	0.01336
2012-01-01	0.01380
2012-04-01	0.01300
2012-07-01	0.01336
2012-10-01	0.01363
2013-01-01	0.01323
2013-04-01	0.01351
2013-07-01	0.01395
2013-10-01	0.01424
2014-01-01	0.01424
2014-04-01	0.01411
2014-07-01	0.01300
2014-10-01	0.01254
2015-01-01	0.01111
2015-04-01	0.01156