Quarter	Billions of US Dollars
1987-01-01	1.433
1987-04-01	1.624
1987-07-01	1.731
1987-10-01	2.140
1988-01-01	2.236
1988-04-01	2.156
1988-07-01	2.259
1988-10-01	2.463
1989-01-01	2.388
1989-04-01	2.413
1989-07-01	2.467
1989-10-01	2.546
1990-01-01	2.431
1990-04-01	2.468
1990-07-01	2.618
1990-10-01	2.664
1991-01-01	2.567
1991-04-01	2.587
1991-07-01	2.807
1991-10-01	2.924
1992-01-01	2.805
1992-04-01	2.850
1992-07-01	3.100
1992-10-01	2.953
1993-01-01	3.075
1993-04-01	3.285
1993-07-01	3.713
1993-10-01	3.607
1994-01-01	4.273
1994-04-01	4.513
1994-07-01	4.873
1994-10-01	4.961
1995-01-01	5.457
1995-04-01	5.395
1995-07-01	4.966
1995-10-01	4.640
1996-01-01	4.767
1996-04-01	4.508
1996-07-01	4.115
1996-10-01	4.026
1997-01-01	4.289
1997-04-01	5.039
1997-07-01	4.877
1997-10-01	4.757
1998-01-01	4.659
1998-04-01	4.041
1998-07-01	3.647
1998-10-01	3.693
1999-01-01	3.223
1999-04-01	3.708
1999-07-01	3.666
1999-10-01	3.909
2000-01-01	3.693
2000-04-01	3.732
2000-07-01	3.643
2000-10-01	3.612
2001-01-01	3.586
2001-04-01	3.460
2001-07-01	3.567
2001-10-01	3.902
2002-01-01	4.899
2002-04-01	4.387
2002-07-01	4.143
2002-10-01	3.870
2003-01-01	3.895
2003-04-01	4.146
2003-07-01	4.390
2003-10-01	5.086
2004-01-01	5.232
2004-04-01	5.271
2004-07-01	6.736
2004-10-01	8.121
2005-01-01	8.232
2005-04-01	8.012
2005-07-01	9.088
2005-10-01	10.359
2006-01-01	10.030
2006-04-01	10.335
2006-07-01	10.110
2006-10-01	9.873
2007-01-01	10.260
2007-04-01	10.558
2007-07-01	12.057
2007-10-01	11.548
2008-01-01	11.917
2008-04-01	12.507
2008-07-01	13.947
2008-10-01	13.691
2009-01-01	13.607
2009-04-01	13.002
2009-07-01	12.534
2009-10-01	12.792
2010-01-01	14.660
2010-04-01	15.046
2010-07-01	14.362
2010-10-01	17.667
2011-01-01	19.112
2011-04-01	25.193
2011-07-01	26.009
2011-10-01	30.617
2012-01-01	39.050
2012-04-01	42.053
2012-07-01	42.789
2012-10-01	48.539
2013-01-01	55.130
2013-04-01	62.017
2013-07-01	69.234
2013-10-01	80.426
2014-01-01	101.672
2014-04-01	119.310
2014-07-01	133.310
2014-10-01	151.367
2015-01-01	152.490
2015-04-01	154.982