Quarter	Billions of US Dollars
1968-04-01	0.015
1971-01-01	0.040
1971-04-01	0.040
1971-07-01	0.002
1971-10-01	0.002
1972-01-01	0.096
1972-04-01	0.102
1972-07-01	0.050
1972-10-01	0.045
1973-01-01	0.097
1973-04-01	0.087
1973-10-01	0.013
1974-01-01	0.144
1974-04-01	0.027
1974-07-01	0.256
1974-10-01	0.164
1975-01-01	0.643
1975-04-01	0.523
1975-07-01	0.311
1975-10-01	0.526
1976-01-01	0.862
1976-04-01	0.904
1976-07-01	0.569
1976-10-01	0.654
1977-01-01	0.495
1977-04-01	0.301
1977-07-01	0.227
1977-10-01	0.797
1978-01-01	0.417
1978-04-01	0.513
1978-07-01	0.382
1978-10-01	0.068
1979-01-01	0.494
1979-04-01	0.619
1979-07-01	0.485
1979-10-01	0.489
1980-01-01	0.053
1980-04-01	0.568
1980-07-01	0.410
1980-10-01	0.958
1981-01-01	0.874
1981-04-01	0.378
1981-07-01	0.259
1981-10-01	0.553
1982-01-01	1.915
1982-04-01	1.784
1982-07-01	1.811
1982-10-01	1.556
1983-01-01	1.929
1983-04-01	1.749
1983-07-01	0.556
1983-10-01	1.563
1984-01-01	2.024
1984-04-01	0.858
1984-07-01	2.597
1984-10-01	1.410
1985-01-01	1.899
1985-04-01	0.606
1985-07-01	1.909
1985-10-01	-0.449
1986-01-01	0.224
1986-04-01	2.349
1986-07-01	1.463
1986-10-01	1.396
1987-01-01	1.215
1987-04-01	1.693
1987-07-01	0.042
1987-10-01	-0.085
1988-01-01	2.525
1988-04-01	4.123
1988-07-01	2.731
1988-10-01	2.292
1989-01-01	3.494
1989-04-01	2.142
1989-07-01	1.871
1989-10-01	1.034
1990-01-01	2.615
1990-04-01	1.767
1990-07-01	3.323
1990-10-01	1.795
1991-01-01	1.910
1991-04-01	3.641
1991-07-01	2.496
1991-10-01	4.526
1992-01-01	3.832
1992-04-01	1.682
1992-07-01	1.101
1992-10-01	6.341
1993-01-01	2.750
1993-04-01	-0.101
1993-07-01	7.456
1993-10-01	4.072
1994-01-01	3.326
1994-04-01	0.704
1994-07-01	2.522
1994-10-01	3.576
1995-01-01	-1.708
1995-04-01	1.570
1995-07-01	0.349
1995-10-01	2.390
1996-01-01	0.127
1996-04-01	3.272
1996-07-01	3.233
1996-10-01	2.154
1997-01-01	4.047
1997-04-01	1.520
1997-07-01	1.337
1997-10-01	0.892
1998-01-01	7.866
1998-04-01	7.214
1998-07-01	7.435
1998-10-01	5.781
1999-01-01	11.299
1999-04-01	15.714
1999-07-01	12.161
1999-10-01	12.913
2000-01-01	11.595
2000-04-01	12.414
2000-07-01	16.755
2000-10-01	13.486
2001-01-01	32.637
2001-04-01	16.607
2001-07-01	18.825
2001-10-01	25.994
2002-01-01	5.698
2002-04-01	19.502
2002-07-01	11.246
2002-10-01	16.178
2003-01-01	23.372
2003-04-01	38.955
2003-07-01	20.738
2003-10-01	28.072
2004-01-01	14.062
2004-04-01	28.203
2004-07-01	20.009
2004-10-01	42.224
2005-01-01	28.635
2005-04-01	47.171
2005-07-01	4.661
2005-10-01	44.203
2006-01-01	36.735
2006-04-01	37.724
2006-07-01	35.839
2006-10-01	75.479
2007-01-01	31.874
2007-04-01	69.003
2007-07-01	8.305
2007-10-01	35.375
2008-01-01	5.897
2008-04-01	76.276
2008-07-01	20.450
2008-10-01	1.919
2009-01-01	14.506
2009-04-01	109.678
2009-07-01	23.418
2009-10-01	35.421
2010-01-01	39.601
2010-04-01	-15.607
2010-07-01	30.259
2010-10-01	23.066
2011-01-01	65.597
2011-04-01	18.530
2011-07-01	-0.177
2011-10-01	17.630
2012-01-01	31.296
2012-04-01	-5.367
2012-07-01	-6.216
2012-10-01	1.310
2013-01-01	-1.106
2013-04-01	3.112
2013-07-01	-6.040
2013-10-01	-5.549
2014-01-01	17.575
2014-04-01	12.572
2014-07-01	1.961
2014-10-01	-14.374
2015-01-01	2.208
2015-04-01	-23.430