Quarter	Billions of US Dollars
1987-01-01	0.03320
1987-04-01	0.03289
1987-07-01	0.03270
1987-10-01	0.03912
1988-01-01	0.03654
1988-04-01	0.03312
1988-07-01	0.03146
1988-10-01	0.07324
1989-01-01	0.07012
1989-04-01	0.06989
1989-07-01	0.07090
1989-10-01	0.07233
1990-01-01	0.07341
1990-04-01	0.07527
1990-07-01	0.07849
1990-10-01	0.07860
1991-01-01	0.07425
1991-04-01	0.07205
1991-07-01	0.07449
1991-10-01	0.07689
1992-01-01	0.07337
1992-04-01	0.07630
1992-07-01	0.08067
1992-10-01	0.07434
1993-01-01	0.07344
1993-04-01	0.07312
1993-07-01	0.04000
1993-10-01	0.04000
1994-01-01	0.04000
1994-04-01	0.04000
1994-07-01	0.04000
1994-10-01	0.04187
1995-01-01	0.04080
1995-04-01	0.04000
1995-07-01	0.04000
1995-10-01	0.04000
1996-01-01	0.06700
1996-04-01	0.15033
1996-07-01	0.15763
1996-10-01	0.19450
1997-01-01	0.22150
1997-04-01	0.27450
1997-07-01	0.26175
1997-10-01	0.36841
1998-01-01	0.42009
1998-04-01	0.39099
1998-07-01	0.38091
1998-10-01	0.35083
1999-01-01	0.41370
1999-04-01	0.26623
1999-07-01	0.28544
1999-10-01	0.48256
2000-01-01	0.44007
2000-04-01	0.39974
2000-07-01	0.34523
2000-10-01	0.21273
2001-01-01	0.20198
2001-04-01	0.23580
2001-07-01	0.22693
2001-10-01	0.13511
2002-01-01	0.12702
2002-04-01	0.12019
2002-07-01	0.09853
2002-10-01	0.06255
2003-01-01	0.11721
2003-04-01	0.12220
2003-07-01	0.13359
2003-10-01	0.22444
2004-01-01	0.39826
2004-04-01	0.47070
2004-07-01	0.72378
2004-10-01	0.81148
2005-01-01	0.88095
2005-04-01	1.06235
2005-07-01	1.47560
2005-10-01	2.15495
2006-01-01	2.30944
2006-04-01	2.21613
2006-07-01	2.27510
2006-10-01	2.17413
2007-01-01	2.24749
2007-04-01	2.43020
2007-07-01	2.87800
2007-10-01	3.51564
2008-01-01	3.96142
2008-04-01	4.19501
2008-07-01	4.34089
2008-10-01	4.01556
2009-01-01	3.43037
2009-04-01	5.04034
2009-07-01	4.94451
2009-10-01	4.52610
2010-01-01	4.58703
2010-04-01	4.61502
2010-07-01	4.46241
2010-10-01	3.70301
2011-01-01	3.60722
2011-04-01	3.87271
2011-07-01	3.88599
2011-10-01	3.86664
2012-01-01	4.15639
2012-04-01	4.93104
2012-07-01	4.46191
2012-10-01	4.70279
2013-01-01	4.88106
2013-04-01	4.23831
2013-07-01	4.18138
2013-10-01	4.17301
2014-01-01	3.95199
2014-04-01	3.14962
2014-07-01	4.43311
2014-10-01	4.53336
2015-01-01	4.94260
2015-04-01	4.74822