Quarter	Billions of US Dollars
1987-01-01	0.516
1987-04-01	0.516
1987-07-01	0.515
1987-10-01	0.537
1988-01-01	0.544
1988-04-01	0.531
1988-07-01	0.521
1988-10-01	0.539
1989-01-01	0.529
1989-04-01	0.528
1989-07-01	1.977
1989-10-01	2.001
1990-01-01	2.042
1990-04-01	2.070
1990-07-01	2.038
1990-10-01	1.875
1991-01-01	1.859
1991-04-01	1.858
1991-07-01	1.894
1991-10-01	1.897
1992-01-01	1.894
1992-04-01	1.898
1992-07-01	1.896
1992-10-01	1.780
1993-01-01	1.780
1993-04-01	1.780
1993-07-01	1.780
1993-10-01	1.780
1994-01-01	1.785
1994-04-01	1.787
1994-07-01	1.789
1994-10-01	1.788
1995-01-01	2.039
1995-04-01	2.019
1995-07-01	2.227
1995-10-01	2.281
1996-01-01	2.382
1996-04-01	2.452
1996-07-01	2.788
1996-10-01	3.127
1997-01-01	3.522
1997-04-01	3.592
1997-07-01	3.683
1997-10-01	3.301
1998-01-01	3.310
1998-04-01	3.527
1998-07-01	3.407
1998-10-01	3.560
1999-01-01	3.398
1999-04-01	3.268
1999-07-01	3.317
1999-10-01	3.515
2000-01-01	5.230
2000-04-01	6.190
2000-07-01	5.995
2000-10-01	5.810
2001-01-01	8.396
2001-04-01	8.018
2001-07-01	8.520
2001-10-01	7.923
2002-01-01	9.264
2002-04-01	9.780
2002-07-01	10.347
2002-10-01	11.406
2003-01-01	13.455
2003-04-01	15.345
2003-07-01	18.567
2003-10-01	22.362
2004-01-01	26.444
2004-04-01	28.938
2004-07-01	35.865
2004-10-01	41.918
2005-01-01	46.004
2005-04-01	50.599
2005-07-01	55.241
2005-10-01	62.982
2006-01-01	68.068
2006-04-01	77.341
2006-07-01	89.683
2006-10-01	103.361
2007-01-01	115.850
2007-04-01	125.595
2007-07-01	137.429
2007-10-01	142.769
2008-01-01	156.895
2008-04-01	155.442
2008-07-01	136.198
2008-10-01	133.875
2009-01-01	122.471
2009-04-01	138.717
2009-07-01	155.502
2009-10-01	162.316
2010-01-01	169.585
2010-04-01	153.028
2010-07-01	123.209
2010-10-01	114.693
2011-01-01	124.223
2011-04-01	120.865
2011-07-01	100.119
2011-10-01	93.784
2012-01-01	85.805
2012-04-01	82.874
2012-07-01	59.144
2012-10-01	62.908
2013-01-01	59.807
2013-04-01	51.250
2013-07-01	48.024
2013-10-01	53.224
2014-01-01	51.369
2014-04-01	51.507
2014-07-01	46.530
2014-10-01	42.098
2015-01-01	36.984
2015-04-01	37.979