Quarter	Billions of US Dollars
1971-01-01	0.0150
1971-10-01	0.0064
1972-01-01	0.0664
1972-04-01	0.0094
1972-07-01	0.0182
1972-10-01	0.0200
1973-01-01	0.0496
1973-04-01	0.0491
1973-07-01	0.0100
1974-01-01	0.0147
1974-07-01	0.0083
1974-10-01	0.0414
1975-01-01	0.1599
1975-04-01	0.3024
1975-07-01	0.1871
1975-10-01	0.4645
1976-01-01	0.4941
1976-04-01	0.2685
1976-07-01	0.2436
1976-10-01	0.3414
1977-01-01	0.8238
1977-04-01	0.8574
1977-07-01	0.1841
1977-10-01	0.7915
1978-01-01	0.8535
1978-04-01	0.7683
1978-07-01	0.3135
1978-10-01	0.6689
1979-01-01	0.6520
1979-04-01	0.4105
1979-07-01	0.5107
1979-10-01	0.2523
1980-01-01	0.4665
1980-04-01	0.1252
1980-07-01	0.0948
1980-10-01	0.1823
1981-01-01	0.0858
1981-04-01	0.1252
1981-07-01	0.1880
1981-10-01	0.1613
1982-01-01	0.0213
1982-04-01	0.2465
1982-07-01	0.2820
1982-10-01	0.2042
1983-01-01	0.3057
1983-04-01	0.0691
1983-07-01	0.0925
1983-10-01	0.1254
1984-01-01	0.1701
1984-04-01	0.2648
1984-07-01	0.3112
1984-10-01	0.2942
1985-01-01	0.4812
1985-04-01	0.3648
1985-07-01	0.8218
1985-10-01	0.7992
1986-01-01	0.7348
1986-04-01	0.6747
1986-07-01	2.2480
1986-10-01	1.8710
1987-01-01	2.6490
1987-04-01	0.5930
1987-07-01	0.4031
1987-10-01	0.1986
1988-01-01	2.5676
1988-04-01	1.5537
1988-07-01	0.6904
1988-10-01	0.5709
1989-01-01	1.1501
1989-04-01	0.3727
1989-07-01	0.3998
1989-10-01	0.7206
1990-01-01	0.2682
1990-04-01	0.1870
1990-07-01	0.1206
1990-10-01	0.2326
1991-01-01	0.3676
1991-04-01	1.5596
1991-07-01	0.3139
1991-10-01	1.0000
1992-01-01	3.2404
1992-04-01	0.4000
1992-07-01	0.5198
1992-10-01	0.2000
1993-01-01	1.5666
1993-04-01	1.8240
1993-10-01	0.2522
1994-01-01	0.2251
1994-04-01	0.1725
1994-07-01	0.4471
1994-10-01	0.2888
1995-01-01	0.1682
1995-04-01	0.2524
1995-07-01	0.6688
1995-10-01	0.9263
1996-01-01	1.2052
1996-04-01	1.0453
1996-07-01	1.7261
1996-10-01	1.3292
1997-01-01	1.4548
1997-04-01	1.0189
1997-07-01	4.4048
1997-10-01	1.1180
1998-01-01	2.6090
1998-04-01	4.1976
1998-07-01	1.1420
1998-10-01	2.3092
1999-01-01	2.6805
1999-04-01	2.0954
1999-07-01	1.2963
1999-10-01	1.6089
2000-01-01	2.2731
2000-04-01	3.1766
2000-07-01	2.0179
2000-10-01	1.1200
2001-01-01	2.7144
2001-04-01	2.6859
2001-07-01	1.1345
2001-10-01	2.6196
2002-01-01	3.1299
2002-04-01	2.1290
2002-07-01	1.3151
2002-10-01	3.9997
2003-01-01	5.2017
2003-04-01	5.8481
2003-07-01	4.8242
2003-10-01	3.4418
2004-01-01	4.5555
2004-04-01	4.5755
2004-07-01	2.3808
2004-10-01	5.6841
2005-01-01	5.5989
2005-04-01	4.9649
2005-07-01	4.6541
2005-10-01	5.6139
2006-01-01	6.4533
2006-04-01	11.5948
2006-07-01	9.4791
2006-10-01	10.7288
2007-01-01	12.8570
2007-04-01	10.4602
2007-07-01	8.5182
2007-10-01	9.3446
2008-01-01	15.3531
2008-04-01	23.2352
2008-07-01	8.0728
2008-10-01	3.2726
2009-01-01	12.0396
2009-04-01	11.9080
2009-07-01	8.5873
2009-10-01	10.8980
2010-01-01	17.1361
2010-04-01	15.1233
2010-07-01	15.0655
2010-10-01	11.9384
2011-01-01	24.5134
2011-04-01	22.5527
2011-07-01	12.5616
2011-10-01	17.6482
2012-01-01	26.4885
2012-04-01	17.5448
2012-07-01	10.9195
2012-10-01	14.2673
2013-01-01	23.2409
2013-04-01	22.9052
2013-07-01	15.8543
2013-10-01	14.9245
2014-01-01	14.0612
2014-04-01	13.6817
2014-07-01	13.3251
2014-10-01	12.6454
2015-01-01	17.1018
2015-04-01	12.1428