Quarter	Billions of US Dollars
1987-01-01	0.242
1987-04-01	0.175
1987-07-01	0.175
1987-10-01	0.194
1988-01-01	0.188
1988-04-01	0.179
1988-07-01	0.100
1988-10-01	0.106
1989-01-01	0.170
1989-04-01	0.161
1989-07-01	0.166
1989-10-01	0.166
1990-01-01	0.159
1990-04-01	0.416
1990-07-01	0.759
1990-10-01	1.220
1991-01-01	1.191
1991-04-01	1.180
1991-07-01	1.200
1991-10-01	1.231
1992-01-01	1.197
1992-04-01	0.961
1992-07-01	0.990
1992-10-01	0.962
1993-01-01	0.952
1993-04-01	0.994
1993-07-01	0.969
1993-10-01	0.852
1994-01-01	0.886
1994-04-01	0.904
1994-07-01	0.907
1994-10-01	0.980
1995-01-01	1.156
1995-04-01	0.784
1995-07-01	0.407
1995-10-01	0.403
1996-01-01	0.526
1996-04-01	0.512
1996-07-01	0.512
1996-10-01	0.973
1997-01-01	1.232
1997-04-01	1.214
1997-07-01	1.208
1997-10-01	2.054
1998-01-01	2.290
1998-04-01	4.094
1998-07-01	4.258
1998-10-01	4.897
1999-01-01	5.535
1999-04-01	7.138
1999-07-01	7.217
1999-10-01	7.757
2000-01-01	8.899
2000-04-01	9.667
2000-07-01	9.226
2000-10-01	10.111
2001-01-01	10.498
2001-04-01	12.364
2001-07-01	14.036
2001-10-01	16.810
2002-01-01	16.989
2002-04-01	23.045
2002-07-01	23.490
2002-10-01	26.229
2003-01-01	31.127
2003-04-01	36.588
2003-07-01	38.560
2003-10-01	52.194
2004-01-01	53.404
2004-04-01	59.560
2004-07-01	62.737
2004-10-01	78.565
2005-01-01	79.617
2005-04-01	87.994
2005-07-01	92.820
2005-10-01	107.445
2006-01-01	131.061
2006-04-01	166.313
2006-07-01	175.720
2006-10-01	196.658
2007-01-01	218.740
2007-04-01	241.393
2007-07-01	270.781
2007-10-01	284.279
2008-01-01	308.753
2008-04-01	333.186
2008-07-01	313.554
2008-10-01	333.634
2009-01-01	348.825
2009-04-01	389.625
2009-07-01	421.874
2009-10-01	427.129
2010-01-01	408.685
2010-04-01	381.343
2010-07-01	439.082
2010-10-01	438.589
2011-01-01	484.583
2011-04-01	502.467
2011-07-01	481.129
2011-10-01	469.685
2012-01-01	522.059
2012-04-01	486.658
2012-07-01	493.247
2012-10-01	522.773
2013-01-01	504.954
2013-04-01	511.869
2013-07-01	525.370
2013-10-01	532.211
2014-01-01	511.428
2014-04-01	505.691
2014-07-01	454.026
2014-10-01	432.503
2015-01-01	385.549
2015-04-01	393.704