Quarter	Billions of US Dollars
1987-01-01	1.513
1987-04-01	1.637
1987-07-01	1.740
1987-10-01	2.737
1988-01-01	2.981
1988-04-01	3.457
1988-07-01	3.623
1988-10-01	3.988
1989-01-01	4.313
1989-04-01	4.678
1989-07-01	5.251
1989-10-01	5.470
1990-01-01	5.745
1990-04-01	6.448
1990-07-01	7.666
1990-10-01	7.825
1991-01-01	8.603
1991-04-01	9.662
1991-07-01	10.002
1991-10-01	10.415
1992-01-01	10.400
1992-04-01	11.272
1992-07-01	12.209
1992-10-01	11.515
1993-01-01	11.813
1993-04-01	12.411
1993-07-01	18.485
1993-10-01	19.803
1994-01-01	22.976
1994-04-01	26.524
1994-07-01	28.756
1994-10-01	32.215
1995-01-01	35.926
1995-04-01	39.757
1995-07-01	42.583
1995-10-01	44.856
1996-01-01	47.486
1996-04-01	50.876
1996-07-01	50.887
1996-10-01	51.970
1997-01-01	54.254
1997-04-01	53.620
1997-07-01	58.597
1997-10-01	59.510
1998-01-01	66.147
1998-04-01	68.640
1998-07-01	73.209
1998-10-01	74.538
1999-01-01	73.976
1999-04-01	78.270
1999-07-01	83.320
1999-10-01	86.684
2000-01-01	96.749
2000-04-01	97.821
2000-07-01	100.021
2000-10-01	107.868
2001-01-01	115.504
2001-04-01	115.362
2001-07-01	121.512
2001-10-01	115.597
2002-01-01	114.898
2002-04-01	137.180
2002-07-01	130.936
2002-10-01	133.326
2003-01-01	141.531
2003-04-01	144.426
2003-07-01	142.892
2003-10-01	149.103
2004-01-01	140.795
2004-04-01	131.936
2004-07-01	131.939
2004-10-01	139.550
2005-01-01	134.965
2005-04-01	122.254
2005-07-01	121.698
2005-10-01	119.439
2006-01-01	128.102
2006-04-01	134.146
2006-07-01	137.366
2006-10-01	146.174
2007-01-01	149.200
2007-04-01	153.776
2007-07-01	152.803
2007-10-01	155.329
2008-01-01	157.538
2008-04-01	148.043
2008-07-01	127.907
2008-10-01	118.413
2009-01-01	113.638
2009-04-01	120.836
2009-07-01	120.865
2009-10-01	112.229
2010-01-01	106.466
2010-04-01	101.301
2010-07-01	107.704
2010-10-01	105.885
2011-01-01	101.339
2011-04-01	102.365
2011-07-01	97.102
2011-10-01	93.217
2012-01-01	101.498
2012-04-01	99.370
2012-07-01	103.702
2012-10-01	108.587
2013-01-01	111.165
2013-04-01	111.951
2013-07-01	112.641
2013-10-01	110.354
2014-01-01	111.579
2014-04-01	111.561
2014-07-01	108.014
2014-10-01	102.053
2015-01-01	94.798
2015-04-01	96.641