Quarter	Billions of US Dollars
1987-01-01	0.22400
1987-04-01	0.19500
1987-07-01	0.18000
1987-10-01	0.17400
1988-01-01	0.24700
1988-04-01	0.24700
1988-07-01	0.24400
1988-10-01	0.30700
1989-01-01	0.29700
1989-04-01	0.34400
1989-07-01	0.14900
1989-10-01	0.08500
1990-01-01	0.04000
1990-04-01	0.01500
1990-07-01	0.01000
1990-10-01	0.08100
1991-01-01	0.07300
1991-10-01	0.04400
1992-01-01	0.04400
1993-10-01	0.01600
1994-01-01	0.01600
1994-04-01	0.02000
1994-07-01	0.02860
1994-10-01	0.04270
1995-01-01	0.03470
1995-04-01	0.02980
1995-07-01	0.02370
1995-10-01	0.08745
1996-01-01	0.10160
1996-04-01	0.19310
1996-07-01	0.28950
1996-10-01	0.27237
1997-01-01	0.34470
1997-04-01	0.35646
1997-07-01	0.32878
1997-10-01	0.34239
1998-01-01	0.28653
1998-04-01	0.19272
1998-07-01	0.08502
1998-10-01	0.02152
1999-01-01	0.01551
1999-04-01	0.01152
1999-07-01	0.00414
1999-10-01	0.00070
2000-01-01	0.00120
2000-04-01	0.00043
2000-07-01	0.00033
2000-10-01	0.00033
2001-01-01	0.00033
2002-10-01	0.02500
2003-01-01	0.12500
2003-04-01	0.12500
2003-07-01	0.10000
2003-10-01	0.15155
2004-01-01	0.22200
2004-04-01	0.45195
2004-07-01	0.59695
2004-10-01	0.62180
2005-01-01	0.55550
2005-04-01	0.67550
2005-07-01	0.37200
2005-10-01	0.42588
2006-01-01	1.16358
2006-04-01	1.24486
2006-07-01	1.54321
2006-10-01	1.19338
2007-01-01	0.76867
2007-04-01	1.15517
2007-07-01	0.86114
2007-10-01	1.99244
2008-01-01	2.42048
2008-04-01	2.64248
2008-07-01	2.80039
2008-10-01	1.77873
2009-01-01	1.46665
2009-04-01	1.50004
2009-07-01	2.09812
2009-10-01	1.50733
2010-01-01	1.54137
2010-04-01	1.57138
2010-07-01	1.46516
2010-10-01	1.16890
2011-01-01	1.24831
2011-04-01	1.61701
2011-07-01	1.46601
2011-10-01	1.41042
2012-01-01	2.95871
2012-04-01	2.95275
2012-07-01	4.08369
2012-10-01	2.07929
2013-01-01	2.20697
2013-04-01	3.00875
2013-07-01	3.76320
2013-10-01	3.17527
2014-01-01	2.89555
2014-04-01	3.70762
2014-07-01	4.05864
2014-10-01	5.71477
2015-01-01	5.73318
2015-04-01	5.36438