Quarter	Billions of US Dollars
1971-01-01	0.0300
1971-04-01	0.0353
1971-10-01	0.0250
1972-01-01	0.0748
1972-04-01	0.0647
1972-07-01	0.0682
1972-10-01	0.0406
1974-04-01	0.0172
1974-07-01	0.0751
1974-10-01	0.0250
1975-01-01	0.2094
1975-04-01	0.2706
1975-07-01	0.0375
1975-10-01	0.0650
1976-01-01	0.0781
1976-04-01	0.2828
1976-07-01	0.4003
1976-10-01	0.2800
1977-01-01	0.0680
1977-04-01	0.0610
1977-07-01	0.4448
1977-10-01	0.3561
1978-01-01	0.5844
1978-04-01	0.2500
1978-07-01	0.3708
1978-10-01	0.2613
1979-01-01	0.2982
1979-04-01	0.0800
1979-07-01	0.0130
1979-10-01	0.1537
1980-01-01	0.2250
1980-07-01	0.1356
1980-10-01	0.0300
1981-01-01	0.1197
1981-04-01	0.0899
1981-07-01	0.0824
1981-10-01	0.4337
1982-01-01	0.5087
1982-04-01	0.2709
1982-07-01	1.0230
1982-10-01	0.4480
1983-01-01	0.1792
1983-04-01	0.4250
1983-07-01	0.5493
1983-10-01	1.0932
1984-01-01	0.6431
1984-04-01	0.9610
1984-07-01	0.6181
1984-10-01	0.9593
1985-01-01	0.8989
1985-04-01	1.6524
1985-07-01	1.2767
1985-10-01	1.7448
1986-01-01	2.6884
1986-04-01	2.0694
1986-07-01	1.7979
1986-10-01	2.8612
1987-01-01	2.1712
1987-04-01	2.0152
1987-07-01	0.8802
1987-10-01	0.8157
1988-01-01	1.2748
1988-04-01	2.4765
1988-07-01	1.3403
1988-10-01	1.9780
1989-01-01	3.2784
1989-04-01	2.2543
1989-07-01	1.1372
1989-10-01	0.7772
1990-01-01	0.5466
1990-04-01	0.7552
1990-07-01	1.6470
1990-10-01	0.6306
1991-01-01	0.5387
1991-04-01	1.2632
1991-07-01	1.4968
1991-10-01	0.6838
1992-01-01	1.7327
1992-04-01	0.4847
1992-07-01	1.6642
1993-01-01	1.3841
1993-04-01	0.9907
1993-07-01	1.8153
1993-10-01	2.7194
1994-01-01	4.0592
1994-04-01	3.3824
1994-07-01	5.4586
1994-10-01	4.2096
1995-01-01	3.2949
1995-04-01	1.5118
1995-07-01	4.5312
1995-10-01	3.9696
1996-01-01	3.8942
1996-04-01	5.8072
1996-07-01	5.5515
1996-10-01	5.0231
1997-01-01	6.1509
1997-04-01	3.9489
1997-07-01	4.1569
1997-10-01	3.3408
1998-01-01	3.3776
1998-04-01	6.2044
1998-07-01	3.3154
1998-10-01	3.1505
1999-01-01	4.7535
1999-04-01	5.2326
1999-07-01	6.6040
1999-10-01	3.9834
2000-01-01	6.6495
2000-04-01	9.8457
2000-07-01	4.7189
2000-10-01	2.3497
2001-01-01	5.4390
2001-04-01	9.4735
2001-07-01	6.9764
2001-10-01	4.2863
2002-01-01	5.8986
2002-04-01	6.0487
2002-07-01	8.1651
2002-10-01	9.1417
2003-01-01	11.1270
2003-04-01	17.2949
2003-07-01	17.7204
2003-10-01	12.3623
2004-01-01	23.4377
2004-04-01	17.5101
2004-07-01	26.2077
2004-10-01	15.7018
2005-01-01	22.2072
2005-04-01	23.0132
2005-07-01	13.1495
2005-10-01	19.2538
2006-01-01	30.4293
2006-04-01	21.5936
2006-07-01	27.5360
2006-10-01	32.4140
2007-01-01	36.5185
2007-04-01	33.3697
2007-07-01	24.1090
2007-10-01	19.2341
2008-01-01	40.4437
2008-04-01	25.6159
2008-07-01	20.7249
2008-10-01	20.8697
2009-01-01	27.5653
2009-04-01	27.2183
2009-07-01	32.9781
2009-10-01	51.3797
2010-01-01	36.4105
2010-04-01	10.8920
2010-07-01	25.6774
2010-10-01	29.8064
2011-01-01	25.5343
2011-04-01	34.7000
2011-07-01	12.7376
2011-10-01	15.1258
2012-01-01	41.4093
2012-04-01	20.3741
2012-07-01	48.4885
2012-10-01	16.8995
2013-01-01	27.1416
2013-04-01	22.9842
2013-07-01	23.7476
2013-10-01	32.0607
2014-01-01	31.5878
2014-04-01	26.6762
2014-07-01	28.8175
2014-10-01	24.2201
2015-01-01	35.5570
2015-04-01	23.1790