Quarter	Billions of US Dollars
1971-01-01	0.058
1971-04-01	0.087
1971-07-01	0.114
1971-10-01	0.166
1972-01-01	0.291
1972-04-01	0.370
1972-07-01	0.484
1972-10-01	0.675
1973-01-01	0.747
1973-04-01	1.121
1973-07-01	1.178
1973-10-01	1.516
1974-01-01	1.663
1974-04-01	2.082
1974-07-01	2.130
1974-10-01	2.262
1975-01-01	2.383
1975-04-01	2.710
1975-07-01	2.755
1975-10-01	2.845
1976-01-01	2.969
1976-04-01	3.174
1976-07-01	3.324
1976-10-01	3.586
1977-01-01	3.789
1977-04-01	4.008
1977-07-01	4.213
1977-10-01	4.572
1978-01-01	5.034
1978-04-01	5.485
1978-07-01	6.036
1978-10-01	6.590
1979-01-01	6.750
1979-04-01	7.035
1979-07-01	7.402
1979-10-01	7.367
1980-01-01	7.049
1980-04-01	7.283
1980-07-01	7.372
1980-10-01	7.147
1981-01-01	7.005
1981-04-01	6.717
1981-07-01	6.845
1981-10-01	6.905
1982-01-01	6.733
1982-04-01	6.775
1982-07-01	6.659
1982-10-01	6.896
1983-01-01	6.963
1983-04-01	6.997
1983-07-01	6.986
1983-10-01	6.944
1984-01-01	6.998
1984-04-01	7.070
1984-07-01	7.047
1984-10-01	7.285
1985-01-01	7.414
1985-04-01	8.208
1985-07-01	8.589
1985-10-01	7.661
1986-01-01	7.622
1986-04-01	7.680
1986-07-01	7.929
1986-10-01	7.755
1987-01-01	7.824
1987-04-01	7.547
1987-07-01	7.171
1987-10-01	7.227
1988-01-01	6.863
1988-04-01	6.300
1988-07-01	6.099
1988-10-01	6.322
1989-01-01	5.869
1989-04-01	5.319
1989-07-01	5.575
1989-10-01	5.716
1990-01-01	5.531
1990-04-01	4.838
1990-07-01	4.619
1990-10-01	4.391
1991-01-01	3.814
1991-04-01	4.565
1991-07-01	4.548
1991-10-01	4.852
1992-01-01	7.174
1992-04-01	7.919
1992-07-01	8.209
1992-10-01	7.589
1993-01-01	7.922
1993-04-01	6.189
1993-07-01	7.609
1993-10-01	8.194
1994-01-01	8.946
1994-04-01	8.657
1994-07-01	8.963
1994-10-01	9.646
1995-01-01	10.308
1995-04-01	10.519
1995-07-01	10.838
1995-10-01	11.297
1996-01-01	11.765
1996-04-01	11.839
1996-07-01	12.442
1996-10-01	14.968
1997-01-01	14.667
1997-04-01	16.154
1997-07-01	17.194
1997-10-01	17.920
1998-01-01	19.627
1998-04-01	20.066
1998-07-01	20.786
1998-10-01	21.399
1999-01-01	22.276
1999-04-01	24.925
1999-07-01	25.898
1999-10-01	26.365
2000-01-01	27.988
2000-04-01	29.717
2000-07-01	30.479
2000-10-01	30.326
2001-01-01	30.432
2001-04-01	32.646
2001-07-01	35.550
2001-10-01	35.515
2002-01-01	36.195
2002-04-01	39.997
2002-07-01	39.928
2002-10-01	41.448
2003-01-01	42.970
2003-04-01	45.633
2003-07-01	50.782
2003-10-01	52.042
2004-01-01	57.919
2004-04-01	59.623
2004-07-01	60.594
2004-10-01	64.602
2005-01-01	65.399
2005-04-01	66.805
2005-07-01	72.561
2005-10-01	77.105
2006-01-01	87.152
2006-04-01	94.428
2006-07-01	97.346
2006-10-01	114.887
2007-01-01	122.987
2007-04-01	133.018
2007-07-01	144.183
2007-10-01	154.650
2008-01-01	154.574
2008-04-01	164.158
2008-07-01	163.950
2008-10-01	160.273
2009-01-01	156.361
2009-04-01	174.595
2009-07-01	187.346
2009-10-01	197.507
2010-01-01	199.000
2010-04-01	200.312
2010-07-01	213.547
2010-10-01	226.448
2011-01-01	239.968
2011-04-01	240.553
2011-07-01	234.523
2011-10-01	250.956
2012-01-01	259.685
2012-04-01	255.810
2012-07-01	265.747
2012-10-01	284.467
2013-01-01	292.501
2013-04-01	297.816
2013-07-01	306.606
2013-10-01	319.785
2014-01-01	323.564
2014-04-01	336.892
2014-07-01	338.237
2014-10-01	341.356
2015-01-01	349.653
2015-04-01	362.725