Quarter	Billions of US Dollars
1987-01-01	1.3616
1987-04-01	1.1039
1987-07-01	1.1042
1987-10-01	1.1495
1988-01-01	1.0518
1988-04-01	1.0009
1988-07-01	0.8155
1988-10-01	0.7216
1989-01-01	0.6385
1989-04-01	0.6540
1989-07-01	0.6001
1989-10-01	0.6088
1990-01-01	0.5808
1990-04-01	0.4290
1990-07-01	0.7839
1990-10-01	2.1649
1991-01-01	0.7082
1991-04-01	0.8302
1991-07-01	1.2801
1991-10-01	2.0239
1992-01-01	1.9646
1992-04-01	2.9774
1992-07-01	3.1750
1992-10-01	4.4134
1993-01-01	4.9004
1993-04-01	7.0741
1993-07-01	13.4278
1993-10-01	15.2053
1994-01-01	17.9077
1994-04-01	17.1703
1994-07-01	17.3281
1994-10-01	18.4336
1995-01-01	15.7805
1995-04-01	15.3962
1995-07-01	16.9310
1995-10-01	17.1284
1996-01-01	17.7382
1996-04-01	19.2947
1996-07-01	18.9290
1996-10-01	19.7807
1997-01-01	19.5901
1997-04-01	20.2852
1997-07-01	22.7908
1997-10-01	20.8328
1998-01-01	23.1272
1998-04-01	25.5777
1998-07-01	23.4302
1998-10-01	22.4979
1999-01-01	20.4017
1999-04-01	20.9143
1999-07-01	20.8108
1999-10-01	20.5110
2000-01-01	21.0481
2000-04-01	21.0259
2000-07-01	19.5003
2000-10-01	18.6536
2001-01-01	18.4708
2001-04-01	18.1553
2001-07-01	17.2873
2001-10-01	17.4847
2002-01-01	16.8150
2002-04-01	16.2935
2002-07-01	15.8027
2002-10-01	14.9537
2003-01-01	16.3053
2003-04-01	16.9676
2003-07-01	16.7995
2003-10-01	15.0026
2004-01-01	14.6694
2004-04-01	13.9278
2004-07-01	13.6574
2004-10-01	13.6795
2005-01-01	13.2247
2005-04-01	12.6436
2005-07-01	12.6167
2005-10-01	12.6690
2006-01-01	12.9847
2006-04-01	12.6653
2006-07-01	13.1891
2006-10-01	13.6586
2007-01-01	13.8091
2007-04-01	16.6868
2007-07-01	17.7576
2007-10-01	18.3706
2008-01-01	20.0118
2008-04-01	19.0422
2008-07-01	17.6154
2008-10-01	16.3200
2009-01-01	16.0555
2009-04-01	20.6301
2009-07-01	21.9161
2009-10-01	24.3966
2010-01-01	28.6363
2010-04-01	31.7171
2010-07-01	36.2952
2010-10-01	42.4984
2011-01-01	50.0880
2011-04-01	57.1928
2011-07-01	57.5492
2011-10-01	58.6504
2012-01-01	60.7266
2012-04-01	60.1117
2012-07-01	65.9721
2012-10-01	70.5160
2013-01-01	74.1530
2013-04-01	75.4161
2013-07-01	77.8506
2013-10-01	77.3269
2014-01-01	79.4924
2014-04-01	82.7174
2014-07-01	85.6308
2014-10-01	84.5243
2015-01-01	80.8615
2015-04-01	80.9821