Quarter	Billions of US Dollars
1972-04-01	0.0254
1972-07-01	0.0250
1972-10-01	0.0250
1973-01-01	0.0282
1973-04-01	0.0521
1973-07-01	0.0528
1973-10-01	0.0473
1974-01-01	0.0503
1974-04-01	0.0502
1974-07-01	0.0487
1974-10-01	0.0532
1975-01-01	0.0550
1975-04-01	0.0545
1975-07-01	0.0483
1975-10-01	0.0491
1976-01-01	0.0501
1976-04-01	0.0528
1976-07-01	0.0626
1976-10-01	0.0647
1977-01-01	0.0640
1977-04-01	0.0649
1977-07-01	0.1088
1977-10-01	0.1182
1978-01-01	0.1230
1978-04-01	0.1933
1978-07-01	0.2069
1978-10-01	0.2614
1979-01-01	0.3527
1979-04-01	0.3493
1979-07-01	0.4072
1979-10-01	0.3976
1980-01-01	0.3645
1980-04-01	0.3803
1980-07-01	0.3789
1980-10-01	0.3715
1981-01-01	0.3523
1981-04-01	0.3240
1981-07-01	0.3246
1981-10-01	0.3423
1982-01-01	0.6268
1982-04-01	0.6534
1982-07-01	0.6389
1982-10-01	0.9744
1983-01-01	1.0285
1983-04-01	1.2349
1983-07-01	2.0809
1983-10-01	2.1834
1984-01-01	2.5225
1984-04-01	2.4830
1984-07-01	2.5991
1984-10-01	3.1743
1985-01-01	3.1757
1985-04-01	4.0397
1985-07-01	4.2049
1985-10-01	5.3632
1986-01-01	5.5056
1986-04-01	5.6375
1986-07-01	5.7791
1986-10-01	5.8295
1987-01-01	6.0139
1987-04-01	6.0738
1987-07-01	6.1557
1987-10-01	6.5621
1988-01-01	6.7016
1988-04-01	6.1629
1988-07-01	6.1506
1988-10-01	6.3092
1989-01-01	6.2757
1989-04-01	5.8650
1989-07-01	5.8544
1989-10-01	6.0774
1990-01-01	5.9948
1990-04-01	6.0590
1990-07-01	6.4822
1990-10-01	6.4185
1991-01-01	6.1717
1991-04-01	6.3069
1991-07-01	6.4600
1991-10-01	6.6534
1992-01-01	6.3468
1992-04-01	6.4671
1992-07-01	6.6356
1992-10-01	5.3289
1993-01-01	5.3973
1993-04-01	5.4830
1993-07-01	4.8283
1993-10-01	4.8653
1994-01-01	5.2134
1994-04-01	5.4007
1994-07-01	5.2196
1994-10-01	5.3547
1995-01-01	5.5769
1995-04-01	5.1612
1995-07-01	6.5308
1995-10-01	6.8276
1996-01-01	7.1355
1996-04-01	7.2943
1996-07-01	7.4223
1996-10-01	9.3508
1997-01-01	9.3298
1997-04-01	11.2496
1997-07-01	11.6933
1997-10-01	11.9230
1998-01-01	11.3928
1998-04-01	11.3039
1998-07-01	11.2067
1998-10-01	11.4632
1999-01-01	11.7616
1999-04-01	12.6146
1999-07-01	13.5092
1999-10-01	13.5380
2000-01-01	13.4631
2000-04-01	13.5494
2000-07-01	13.8005
2000-10-01	14.6840
2001-01-01	14.4825
2001-04-01	15.2103
2001-07-01	16.2492
2001-10-01	16.0401
2002-01-01	17.1922
2002-04-01	20.2633
2002-07-01	20.6272
2002-10-01	21.8757
2003-01-01	21.8444
2003-04-01	21.9846
2003-07-01	21.2858
2003-10-01	20.9140
2004-01-01	20.8992
2004-04-01	20.8260
2004-07-01	22.3408
2004-10-01	23.0080
2005-01-01	23.0902
2005-04-01	23.7630
2005-07-01	24.1776
2005-10-01	23.5624
2006-01-01	24.6886
2006-04-01	24.5458
2006-07-01	24.7476
2006-10-01	24.9656
2007-01-01	24.8030
2007-04-01	23.7440
2007-07-01	23.6913
2007-10-01	23.9002
2008-01-01	25.0257
2008-04-01	24.9998
2008-07-01	25.2948
2008-10-01	24.6856
2009-01-01	24.0148
2009-04-01	21.2595
2009-07-01	24.4772
2009-10-01	23.6430
2010-01-01	23.9965
2010-04-01	25.4470
2010-07-01	26.7309
2010-10-01	26.5125
2011-01-01	26.7444
2011-04-01	26.9379
2011-07-01	27.0534
2011-10-01	26.9620
2012-01-01	28.0790
2012-04-01	30.9056
2012-07-01	32.0816
2012-10-01	32.5820
2013-01-01	32.4370
2013-04-01	35.6114
2013-07-01	35.7794
2013-10-01	36.4683
2014-01-01	37.0020
2014-04-01	37.6414
2014-07-01	36.5460
2014-10-01	38.4397
2015-01-01	42.6148
2015-04-01	43.5428