Quarter	Billions of US Dollars
1987-04-01	0.0400
1987-07-01	0.0490
1987-10-01	0.0280
1988-01-01	0.0840
1988-04-01	0.1750
1988-07-01	0.1530
1988-10-01	0.1150
1989-01-01	0.1410
1989-04-01	0.1420
1989-07-01	0.1440
1989-10-01	0.0750
1990-01-01	0.0750
1992-01-01	0.1100
1992-04-01	0.0600
1992-07-01	0.0470
1992-10-01	0.0930
1993-01-01	0.0690
1993-04-01	0.2280
1993-07-01	0.4400
1993-10-01	0.4355
1994-01-01	0.6182
1994-04-01	0.7147
1994-07-01	0.8833
1994-10-01	0.6298
1995-01-01	0.6648
1995-04-01	0.6886
1995-07-01	0.7873
1995-10-01	0.9544
1996-01-01	0.6639
1996-04-01	0.6199
1996-07-01	1.2217
1996-10-01	1.1982
1997-01-01	1.3172
1997-04-01	1.7851
1997-07-01	1.5081
1997-10-01	1.4084
1998-01-01	1.7328
1998-04-01	1.4596
1998-07-01	1.7732
1998-10-01	1.8034
1999-01-01	1.7337
1999-04-01	1.3674
1999-07-01	1.1974
1999-10-01	1.3712
2000-01-01	1.3143
2000-04-01	1.8005
2000-07-01	1.8388
2000-10-01	1.9860
2001-01-01	2.1015
2001-04-01	2.2515
2001-07-01	2.2258
2001-10-01	2.0740
2002-01-01	2.3304
2002-04-01	2.6134
2002-07-01	2.6964
2002-10-01	2.6655
2003-01-01	2.7831
2003-04-01	2.1508
2003-07-01	1.7971
2003-10-01	1.5781
2004-01-01	1.6180
2004-04-01	1.3037
2004-07-01	1.2512
2004-10-01	1.4895
2005-01-01	1.5954
2005-04-01	1.9514
2005-07-01	2.3575
2005-10-01	2.3022
2006-01-01	2.8264
2006-04-01	3.5230
2006-07-01	3.6046
2006-10-01	3.7660
2007-01-01	4.3660
2007-04-01	4.8825
2007-07-01	4.8440
2007-10-01	4.7698
2008-01-01	4.6343
2008-04-01	4.5093
2008-07-01	4.6268
2008-10-01	4.4658
2009-01-01	5.0998
2009-04-01	5.2586
2009-07-01	6.3707
2009-10-01	6.5360
2010-01-01	6.6541
2010-04-01	6.4525
2010-07-01	7.2540
2010-10-01	7.3512
2011-01-01	7.3583
2011-04-01	7.9216
2011-07-01	6.8102
2011-10-01	7.2096
2012-01-01	7.5345
2012-04-01	8.4148
2012-07-01	8.3335
2012-10-01	8.3559
2013-01-01	8.4688
2013-04-01	9.2852
2013-07-01	9.2784
2013-10-01	9.7303
2014-01-01	11.5573
2014-04-01	13.2424
2014-07-01	12.5852
2014-10-01	13.2805
2015-01-01	13.8357
2015-04-01	12.1726