Quarter	Billions of US Dollars
1987-01-01	0.507
1987-04-01	0.760
1987-07-01	0.760
1987-10-01	0.818
1988-01-01	1.108
1988-04-01	1.079
1988-07-01	1.018
1988-10-01	1.008
1989-01-01	0.990
1989-04-01	0.954
1989-07-01	0.963
1989-10-01	0.943
1990-01-01	0.634
1990-04-01	0.627
1990-07-01	0.651
1990-10-01	0.728
1991-01-01	0.688
1991-04-01	0.660
1991-07-01	0.952
1991-10-01	0.988
1992-01-01	0.968
1992-04-01	1.269
1992-07-01	1.293
1992-10-01	1.381
1993-01-01	1.345
1993-04-01	0.992
1993-07-01	1.293
1993-10-01	1.269
1994-01-01	1.242
1994-04-01	1.149
1994-07-01	0.847
1994-10-01	0.885
1995-01-01	1.159
1995-04-01	0.901
1995-07-01	0.874
1995-10-01	0.741
1996-01-01	0.671
1996-04-01	0.656
1996-07-01	0.519
1996-10-01	0.503
1997-01-01	0.958
1997-04-01	0.917
1997-07-01	0.894
1997-10-01	0.686
1998-01-01	0.644
1998-04-01	0.861
1998-07-01	1.342
1998-10-01	1.286
1999-01-01	1.540
1999-04-01	2.234
1999-07-01	3.829
1999-10-01	9.009
2000-01-01	9.009
2000-04-01	10.517
2000-07-01	14.792
2000-10-01	19.711
2001-01-01	22.071
2001-04-01	29.283
2001-07-01	34.983
2001-10-01	47.466
2002-01-01	47.772
2002-04-01	60.527
2002-07-01	63.927
2002-10-01	80.390
2003-01-01	94.572
2003-04-01	104.128
2003-07-01	107.825
2003-10-01	121.969
2004-01-01	123.904
2004-04-01	127.190
2004-07-01	128.417
2004-10-01	147.789
2005-01-01	139.608
2005-04-01	142.559
2005-07-01	141.036
2005-10-01	150.354
2006-01-01	156.870
2006-04-01	167.932
2006-07-01	171.402
2006-10-01	188.691
2007-01-01	198.957
2007-04-01	214.579
2007-07-01	225.040
2007-10-01	233.663
2008-01-01	253.491
2008-04-01	255.479
2008-07-01	251.523
2008-10-01	302.588
2009-01-01	308.880
2009-04-01	333.823
2009-07-01	364.593
2009-10-01	371.057
2010-01-01	343.755
2010-04-01	312.185
2010-07-01	347.970
2010-10-01	345.034
2011-01-01	364.123
2011-04-01	369.484
2011-07-01	340.312
2011-10-01	334.636
2012-01-01	316.724
2012-04-01	291.063
2012-07-01	293.437
2012-10-01	294.965
2013-01-01	281.533
2013-04-01	284.507
2013-07-01	297.220
2013-10-01	309.629
2014-01-01	311.657
2014-04-01	321.354
2014-07-01	294.933
2014-10-01	290.315
2015-01-01	261.774
2015-04-01	276.751