Quarter	Billions of US Dollars
1987-01-01	0.0070
1988-07-01	0.1430
1988-10-01	0.0610
1989-01-01	0.1420
1989-04-01	0.1160
1989-07-01	0.1150
1989-10-01	0.0810
1990-01-01	0.0580
1990-04-01	0.1000
1990-07-01	0.1760
1990-10-01	0.0870
1991-01-01	0.1990
1991-04-01	0.3310
1991-07-01	0.2730
1991-10-01	0.1520
1992-01-01	0.1590
1992-04-01	0.2710
1992-07-01	0.2600
1992-10-01	0.1580
1993-01-01	0.1160
1993-04-01	0.2680
1993-07-01	0.7036
1993-10-01	0.7285
1994-01-01	1.1551
1994-04-01	1.6899
1994-07-01	1.5430
1994-10-01	1.1556
1995-01-01	1.7633
1995-04-01	1.9185
1995-07-01	1.9668
1995-10-01	1.4310
1996-01-01	2.3128
1996-04-01	2.5705
1996-07-01	4.1785
1996-10-01	3.7051
1997-01-01	4.8058
1997-04-01	7.8744
1997-07-01	7.2686
1997-10-01	5.9632
1998-01-01	5.6396
1998-04-01	5.3241
1998-07-01	5.3286
1998-10-01	5.2559
1999-01-01	5.8887
1999-04-01	5.2713
1999-07-01	6.7969
1999-10-01	7.3291
2000-01-01	7.6067
2000-04-01	8.8786
2000-07-01	7.9503
2000-10-01	9.5595
2001-01-01	8.6374
2001-04-01	11.6206
2001-07-01	8.3900
2001-10-01	9.4806
2002-01-01	8.3615
2002-04-01	8.5097
2002-07-01	8.3212
2002-10-01	9.1918
2003-01-01	10.4175
2003-04-01	10.1137
2003-07-01	8.9169
2003-10-01	11.1489
2004-01-01	15.0231
2004-04-01	12.4296
2004-07-01	11.7653
2004-10-01	13.0319
2005-01-01	14.8506
2005-04-01	15.0194
2005-07-01	14.6404
2005-10-01	14.7387
2006-01-01	16.4086
2006-04-01	20.5494
2006-07-01	22.8598
2006-10-01	25.7653
2007-01-01	30.4910
2007-04-01	25.4300
2007-07-01	35.3467
2007-10-01	29.3365
2008-01-01	40.2940
2008-04-01	43.3012
2008-07-01	31.9726
2008-10-01	17.2647
2009-01-01	16.7109
2009-04-01	17.3443
2009-07-01	16.2885
2009-10-01	11.9483
2010-01-01	10.3286
2010-04-01	10.9873
2010-07-01	9.0096
2010-10-01	10.5380
2011-01-01	12.2293
2011-04-01	14.2638
2011-07-01	16.1403
2011-10-01	14.6565
2012-01-01	15.1730
2012-04-01	12.0367
2012-07-01	12.7700
2012-10-01	9.4827
2013-01-01	10.9522
2013-04-01	16.1648
2013-07-01	13.6192
2013-10-01	15.5941
2014-01-01	19.3443
2014-04-01	25.1973
2014-07-01	30.7010
2014-10-01	30.7820
2015-01-01	29.8765
2015-04-01	30.2648