Quarter	Billions of US Dollars
1987-01-01	9.549
1987-04-01	9.389
1987-07-01	9.195
1987-10-01	10.056
1988-01-01	9.692
1988-04-01	9.408
1988-07-01	9.890
1988-10-01	10.338
1989-01-01	10.338
1989-04-01	10.122
1989-07-01	10.645
1989-10-01	11.054
1990-01-01	11.181
1990-04-01	10.920
1990-07-01	12.373
1990-10-01	14.271
1991-01-01	12.790
1991-04-01	13.732
1991-07-01	14.908
1991-10-01	16.301
1992-01-01	16.391
1992-04-01	18.246
1992-07-01	19.509
1992-10-01	20.023
1993-01-01	21.393
1993-04-01	22.866
1993-07-01	30.247
1993-10-01	31.877
1994-01-01	35.938
1994-04-01	36.689
1994-07-01	38.373
1994-10-01	40.049
1995-01-01	40.076
1995-04-01	41.441
1995-07-01	42.452
1995-10-01	44.176
1996-01-01	46.507
1996-04-01	49.687
1996-07-01	52.570
1996-10-01	57.903
1997-01-01	59.815
1997-04-01	64.244
1997-07-01	68.607
1997-10-01	65.095
1998-01-01	65.730
1998-04-01	66.959
1998-07-01	63.844
1998-10-01	62.913
1999-01-01	59.242
1999-04-01	58.567
1999-07-01	57.594
1999-10-01	57.678
2000-01-01	59.178
2000-04-01	58.256
2000-07-01	55.162
2000-10-01	52.525
2001-01-01	50.905
2001-04-01	49.354
2001-07-01	45.557
2001-10-01	46.064
2002-01-01	44.647
2002-04-01	45.201
2002-07-01	44.917
2002-10-01	44.829
2003-01-01	47.222
2003-04-01	51.206
2003-07-01	53.529
2003-10-01	55.511
2004-01-01	61.304
2004-04-01	62.000
2004-07-01	64.919
2004-10-01	69.893
2005-01-01	74.388
2005-04-01	76.352
2005-07-01	80.778
2005-10-01	88.968
2006-01-01	93.834
2006-04-01	102.329
2006-07-01	111.519
2006-10-01	122.482
2007-01-01	135.445
2007-04-01	151.413
2007-07-01	157.929
2007-10-01	163.660
2008-01-01	174.837
2008-04-01	178.355
2008-07-01	174.626
2008-10-01	160.049
2009-01-01	156.823
2009-04-01	168.557
2009-07-01	174.244
2009-10-01	173.548
2010-01-01	172.592
2010-04-01	171.934
2010-07-01	185.194
2010-10-01	196.588
2011-01-01	213.579
2011-04-01	224.404
2011-07-01	221.250
2011-10-01	226.137
2012-01-01	234.833
2012-04-01	239.612
2012-07-01	270.823
2012-10-01	291.522
2013-01-01	306.224
2013-04-01	319.130
2013-07-01	333.726
2013-10-01	347.937
2014-01-01	357.236
2014-04-01	375.562
2014-07-01	386.330
2014-10-01	419.170
2015-01-01	417.917
2015-04-01	431.970