Quarter	Billions of US Dollars
1987-01-01	1.254
1987-04-01	1.032
1987-07-01	1.032
1987-10-01	1.077
1988-01-01	0.980
1988-04-01	0.929
1988-07-01	0.743
1988-10-01	0.650
1989-01-01	0.566
1989-04-01	0.614
1989-07-01	0.560
1989-10-01	0.569
1990-01-01	0.541
1990-04-01	0.429
1990-07-01	0.360
1990-10-01	1.738
1991-01-01	0.340
1991-04-01	0.465
1991-07-01	0.773
1991-10-01	1.330
1992-01-01	0.936
1992-04-01	1.874
1992-07-01	1.916
1992-10-01	2.648
1993-01-01	3.225
1993-04-01	5.210
1993-07-01	11.614
1993-10-01	13.264
1994-01-01	15.704
1994-04-01	16.825
1994-07-01	17.340
1994-10-01	17.968
1995-01-01	15.871
1995-04-01	16.330
1995-07-01	17.378
1995-10-01	17.597
1996-01-01	19.326
1996-04-01	23.510
1996-07-01	19.968
1996-10-01	20.731
1997-01-01	21.178
1997-04-01	20.939
1997-07-01	24.038
1997-10-01	21.240
1998-01-01	23.490
1998-04-01	25.476
1998-07-01	22.963
1998-10-01	20.469
1999-01-01	18.930
1999-04-01	19.339
1999-07-01	19.429
1999-10-01	19.807
2000-01-01	20.902
2000-04-01	19.226
2000-07-01	19.034
2000-10-01	19.553
2001-01-01	19.383
2001-04-01	19.537
2001-07-01	17.256
2001-10-01	16.819
2002-01-01	16.381
2002-04-01	16.523
2002-07-01	15.597
2002-10-01	15.629
2003-01-01	17.518
2003-04-01	18.326
2003-07-01	18.055
2003-10-01	17.774
2004-01-01	17.596
2004-04-01	17.525
2004-07-01	17.384
2004-10-01	17.047
2005-01-01	16.272
2005-04-01	16.527
2005-07-01	16.139
2005-10-01	17.704
2006-01-01	19.708
2006-04-01	20.048
2006-07-01	20.443
2006-10-01	21.333
2007-01-01	23.862
2007-04-01	26.627
2007-07-01	25.816
2007-10-01	26.342
2008-01-01	27.932
2008-04-01	27.239
2008-07-01	25.120
2008-10-01	24.479
2009-01-01	23.523
2009-04-01	24.654
2009-07-01	26.381
2009-10-01	28.526
2010-01-01	33.669
2010-04-01	37.668
2010-07-01	44.247
2010-10-01	47.558
2011-01-01	53.347
2011-04-01	61.596
2011-07-01	61.768
2011-10-01	63.522
2012-01-01	73.927
2012-04-01	76.828
2012-07-01	84.958
2012-10-01	94.656
2013-01-01	101.989
2013-04-01	104.347
2013-07-01	108.634
2013-10-01	108.444
2014-01-01	110.858
2014-04-01	115.300
2014-07-01	117.185
2014-10-01	115.807
2015-01-01	107.712
2015-04-01	109.862