Quarter	Billions of US Dollars
1987-01-01	0.767
1987-04-01	0.744
1987-07-01	0.715
1987-10-01	0.768
1988-01-01	0.626
1988-04-01	0.600
1988-07-01	0.589
1988-10-01	0.606
1989-01-01	0.509
1989-04-01	0.500
1989-07-01	0.507
1989-10-01	0.515
1990-01-01	0.488
1990-04-01	1.121
1990-07-01	1.239
1990-10-01	1.576
1991-01-01	2.426
1991-04-01	2.473
1991-07-01	2.559
1991-10-01	2.810
1992-01-01	3.032
1992-04-01	3.129
1992-07-01	3.336
1992-10-01	3.714
1993-01-01	3.713
1993-04-01	3.817
1993-07-01	4.523
1993-10-01	5.581
1994-01-01	6.304
1994-04-01	7.349
1994-07-01	8.204
1994-10-01	8.494
1995-01-01	7.833
1995-04-01	8.001
1995-07-01	8.447
1995-10-01	8.485
1996-01-01	8.667
1996-04-01	9.513
1996-07-01	10.226
1996-10-01	9.840
1997-01-01	9.649
1997-04-01	11.729
1997-07-01	12.134
1997-10-01	12.157
1998-01-01	11.999
1998-04-01	14.439
1998-07-01	15.503
1998-10-01	16.380
1999-01-01	16.876
1999-04-01	18.170
1999-07-01	19.639
1999-10-01	20.018
2000-01-01	21.257
2000-04-01	20.040
2000-07-01	19.947
2000-10-01	19.455
2001-01-01	19.733
2001-04-01	20.268
2001-07-01	21.826
2001-10-01	23.477
2002-01-01	26.433
2002-04-01	27.236
2002-07-01	29.248
2002-10-01	30.249
2003-01-01	31.575
2003-04-01	34.641
2003-07-01	38.649
2003-10-01	39.153
2004-01-01	39.917
2004-04-01	41.481
2004-07-01	43.389
2004-10-01	44.376
2005-01-01	44.799
2005-04-01	42.536
2005-07-01	43.646
2005-10-01	44.484
2006-01-01	45.921
2006-04-01	46.687
2006-07-01	46.785
2006-10-01	53.809
2007-01-01	58.901
2007-04-01	62.573
2007-07-01	59.474
2007-10-01	64.677
2008-01-01	67.356
2008-04-01	73.263
2008-07-01	72.495
2008-10-01	69.421
2009-01-01	67.291
2009-04-01	67.189
2009-07-01	71.316
2009-10-01	81.343
2010-01-01	83.262
2010-04-01	81.901
2010-07-01	88.639
2010-10-01	87.868
2011-01-01	96.752
2011-04-01	100.098
2011-07-01	99.000
2011-10-01	102.146
2012-01-01	116.662
2012-04-01	118.795
2012-07-01	121.877
2012-10-01	126.192
2013-01-01	128.039
2013-04-01	142.873
2013-07-01	145.063
2013-10-01	144.864
2014-01-01	159.537
2014-04-01	171.781
2014-07-01	171.803
2014-10-01	168.885
2015-01-01	164.909
2015-04-01	166.658