Quarter	Billions of US Dollars
1987-01-01	0.1870
1987-04-01	0.2350
1987-07-01	0.2520
1987-10-01	0.3690
1988-01-01	1.1910
1988-04-01	1.5410
1988-07-01	1.6660
1988-10-01	1.5340
1989-01-01	0.9280
1989-04-01	0.8620
1989-07-01	1.0500
1989-10-01	0.9660
1990-01-01	0.7100
1990-04-01	1.1520
1990-07-01	0.9990
1990-10-01	0.9650
1991-01-01	0.7600
1991-04-01	0.9520
1991-07-01	0.8490
1991-10-01	0.9210
1992-01-01	1.8630
1992-04-01	1.8390
1992-07-01	0.9470
1992-10-01	0.8990
1993-01-01	0.8960
1993-04-01	0.9440
1993-07-01	1.8038
1993-10-01	2.0902
1994-01-01	2.1240
1994-04-01	1.9240
1994-07-01	2.0910
1994-10-01	1.7907
1995-01-01	1.9958
1995-04-01	2.0569
1995-07-01	1.5193
1995-10-01	1.7639
1996-01-01	1.7291
1996-04-01	3.1380
1996-07-01	2.9528
1996-10-01	2.7675
1997-01-01	2.7908
1997-04-01	4.4248
1997-07-01	3.5543
1997-10-01	4.4978
1998-01-01	5.4564
1998-04-01	5.7211
1998-07-01	6.9496
1998-10-01	7.6353
1999-01-01	7.1618
1999-04-01	7.8421
1999-07-01	7.7533
1999-10-01	7.4919
2000-01-01	6.3084
2000-04-01	5.4004
2000-07-01	5.2043
2000-10-01	6.0993
2001-01-01	4.9460
2001-04-01	3.7609
2001-07-01	3.5402
2001-10-01	4.1261
2002-01-01	4.8163
2002-04-01	4.3778
2002-07-01	4.6847
2002-10-01	5.7739
2003-01-01	6.1023
2003-04-01	5.7431
2003-07-01	4.6114
2003-10-01	4.7121
2004-01-01	4.7057
2004-04-01	4.3474
2004-07-01	4.1135
2004-10-01	4.3857
2005-01-01	4.5833
2005-04-01	3.8689
2005-07-01	3.2959
2005-10-01	3.3821
2006-01-01	2.6396
2006-04-01	4.0795
2006-07-01	4.5876
2006-10-01	5.4588
2007-01-01	6.0621
2007-04-01	8.2616
2007-07-01	6.0698
2007-10-01	4.8567
2008-01-01	5.5262
2008-04-01	5.9193
2008-07-01	5.1266
2008-10-01	4.6464
2009-01-01	3.7187
2009-04-01	7.2198
2009-07-01	5.8958
2009-10-01	5.5409
2010-01-01	5.8347
2010-04-01	5.4266
2010-07-01	5.0193
2010-10-01	3.5378
2011-01-01	3.7697
2011-04-01	3.4856
2011-07-01	4.2342
2011-10-01	4.2815
2012-01-01	6.1112
2012-04-01	5.6059
2012-07-01	4.9902
2012-10-01	6.0473
2013-01-01	5.6393
2013-04-01	5.2697
2013-07-01	8.3217
2013-10-01	14.3951
2014-01-01	12.5956
2014-04-01	16.0078
2014-07-01	15.7212
2014-10-01	12.5475
2015-01-01	12.0897
2015-04-01	14.1990