Quarter	Billions of US Dollars
1977-04-01	0.050
1977-07-01	0.050
1977-10-01	0.050
1978-01-01	0.050
1978-04-01	0.050
1978-07-01	0.050
1978-10-01	0.050
1979-01-01	0.050
1979-04-01	0.050
1979-07-01	0.050
1979-10-01	0.050
1980-01-01	0.050
1980-04-01	0.080
1980-07-01	0.080
1980-10-01	0.080
1981-01-01	0.080
1981-04-01	0.080
1981-07-01	0.080
1981-10-01	0.080
1982-01-01	0.080
1982-04-01	0.030
1982-07-01	0.049
1982-10-01	0.076
1983-01-01	0.096
1983-04-01	0.095
1983-07-01	0.096
1983-10-01	0.126
1984-01-01	0.250
1984-04-01	0.368
1984-07-01	0.403
1984-10-01	0.438
1985-01-01	0.477
1985-04-01	0.540
1985-07-01	0.731
1985-10-01	0.824
1986-01-01	0.965
1986-04-01	1.194
1986-07-01	1.436
1986-10-01	1.458
1987-01-01	1.666
1987-04-01	1.823
1987-07-01	2.171
1987-10-01	2.508
1988-01-01	2.909
1988-04-01	3.358
1988-07-01	3.385
1988-10-01	4.229
1989-01-01	4.062
1989-04-01	3.906
1989-07-01	4.025
1989-10-01	4.020
1990-01-01	3.950
1990-04-01	4.025
1990-07-01	4.265
1990-10-01	3.599
1991-01-01	2.600
1991-04-01	2.584
1991-07-01	2.710
1991-10-01	3.085
1992-01-01	2.867
1992-04-01	3.165
1992-07-01	3.061
1992-10-01	2.697
1993-01-01	3.305
1993-04-01	3.065
1993-07-01	4.298
1993-10-01	5.077
1994-01-01	5.995
1994-04-01	6.072
1994-07-01	7.739
1994-10-01	8.144
1995-01-01	9.722
1995-04-01	11.114
1995-07-01	10.629
1995-10-01	10.833
1996-01-01	11.445
1996-04-01	12.602
1996-07-01	12.384
1996-10-01	12.604
1997-01-01	12.160
1997-04-01	13.051
1997-07-01	13.772
1997-10-01	14.385
1998-01-01	15.013
1998-04-01	15.828
1998-07-01	16.779
1998-10-01	17.034
1999-01-01	15.186
1999-04-01	18.046
1999-07-01	19.629
1999-10-01	21.154
2000-01-01	21.819
2000-04-01	23.703
2000-07-01	25.150
2000-10-01	27.269
2001-01-01	30.017
2001-04-01	33.106
2001-07-01	37.015
2001-10-01	39.533
2002-01-01	40.998
2002-04-01	50.658
2002-07-01	49.642
2002-10-01	54.684
2003-01-01	59.255
2003-04-01	64.236
2003-07-01	67.320
2003-10-01	81.245
2004-01-01	80.219
2004-04-01	82.990
2004-07-01	86.099
2004-10-01	97.107
2005-01-01	95.862
2005-04-01	91.202
2005-07-01	89.657
2005-10-01	101.613
2006-01-01	109.915
2006-04-01	115.614
2006-07-01	120.748
2006-10-01	135.507
2007-01-01	138.688
2007-04-01	152.624
2007-07-01	160.051
2007-10-01	170.804
2008-01-01	189.233
2008-04-01	195.603
2008-07-01	179.786
2008-10-01	181.776
2009-01-01	190.009
2009-04-01	213.686
2009-07-01	231.401
2009-10-01	229.906
2010-01-01	223.640
2010-04-01	202.446
2010-07-01	223.496
2010-10-01	221.150
2011-01-01	231.501
2011-04-01	223.977
2011-07-01	206.116
2011-10-01	199.359
2012-01-01	196.139
2012-04-01	178.678
2012-07-01	172.294
2012-10-01	176.716
2013-01-01	169.790
2013-04-01	168.235
2013-07-01	172.208
2013-10-01	175.313
2014-01-01	172.676
2014-04-01	158.141
2014-07-01	148.979
2014-10-01	136.690
2015-01-01	118.571
2015-04-01	122.080