Quarter	Billions of US Dollars
1972-04-01	0.037
1972-07-01	0.036
1972-10-01	0.086
1973-01-01	0.091
1973-04-01	0.137
1973-07-01	0.137
1973-10-01	0.148
1974-01-01	0.170
1974-04-01	0.187
1974-07-01	0.184
1974-10-01	0.213
1975-01-01	0.242
1975-04-01	0.241
1975-07-01	0.228
1975-10-01	0.248
1976-01-01	0.251
1976-04-01	0.263
1976-07-01	0.667
1976-10-01	0.722
1977-01-01	0.809
1977-04-01	0.850
1977-07-01	0.941
1977-10-01	1.015
1978-01-01	1.221
1978-04-01	1.385
1978-07-01	1.571
1978-10-01	1.709
1979-01-01	1.935
1979-04-01	2.030
1979-07-01	2.266
1979-10-01	2.230
1980-01-01	2.134
1980-04-01	2.326
1980-07-01	2.468
1980-10-01	2.501
1981-01-01	2.427
1981-04-01	2.378
1981-07-01	2.516
1981-10-01	2.767
1982-01-01	3.063
1982-04-01	3.301
1982-07-01	3.265
1982-10-01	3.931
1983-01-01	3.946
1983-04-01	4.165
1983-07-01	5.504
1983-10-01	5.685
1984-01-01	6.179
1984-04-01	6.080
1984-07-01	6.350
1984-10-01	7.353
1985-01-01	8.091
1985-04-01	9.657
1985-07-01	10.871
1985-10-01	13.247
1986-01-01	15.157
1986-04-01	16.269
1986-07-01	17.026
1986-10-01	17.138
1987-01-01	18.225
1987-04-01	18.367
1987-07-01	18.885
1987-10-01	21.178
1988-01-01	20.824
1988-04-01	19.926
1988-07-01	20.482
1988-10-01	21.630
1989-01-01	20.873
1989-04-01	20.013
1989-07-01	20.318
1989-10-01	21.063
1990-01-01	20.625
1990-04-01	21.267
1990-07-01	22.875
1990-10-01	23.485
1991-01-01	23.393
1991-04-01	25.189
1991-07-01	26.256
1991-10-01	27.903
1992-01-01	27.394
1992-04-01	28.771
1992-07-01	31.104
1992-10-01	32.918
1993-01-01	33.766
1993-04-01	35.824
1993-07-01	37.750
1993-10-01	41.739
1994-01-01	46.303
1994-04-01	51.014
1994-07-01	55.692
1994-10-01	57.024
1995-01-01	60.341
1995-04-01	62.799
1995-07-01	64.983
1995-10-01	66.635
1996-01-01	70.226
1996-04-01	75.080
1996-07-01	83.511
1996-10-01	93.055
1997-01-01	98.439
1997-04-01	109.903
1997-07-01	116.817
1997-10-01	118.538
1998-01-01	117.836
1998-04-01	121.045
1998-07-01	119.344
1998-10-01	120.895
1999-01-01	119.795
1999-04-01	120.086
1999-07-01	119.026
1999-10-01	119.316
2000-01-01	121.718
2000-04-01	119.721
2000-07-01	117.566
2000-10-01	116.778
2001-01-01	113.210
2001-04-01	114.925
2001-07-01	112.573
2001-10-01	113.873
2002-01-01	116.334
2002-04-01	123.637
2002-07-01	125.365
2002-10-01	128.369
2003-01-01	130.641
2003-04-01	135.738
2003-07-01	142.405
2003-10-01	146.262
2004-01-01	154.522
2004-04-01	160.678
2004-07-01	165.684
2004-10-01	173.639
2005-01-01	178.506
2005-04-01	182.623
2005-07-01	187.907
2005-10-01	193.232
2006-01-01	203.000
2006-04-01	207.535
2006-07-01	213.369
2006-10-01	218.968
2007-01-01	226.309
2007-04-01	237.975
2007-07-01	240.191
2007-10-01	246.619
2008-01-01	253.582
2008-04-01	254.084
2008-07-01	251.481
2008-10-01	246.562
2009-01-01	249.097
2009-04-01	255.783
2009-07-01	269.760
2009-10-01	273.978
2010-01-01	277.975
2010-04-01	280.073
2010-07-01	288.061
2010-10-01	300.748
2011-01-01	310.800
2011-04-01	322.800
2011-07-01	327.142
2011-10-01	330.020
2012-01-01	343.349
2012-04-01	358.296
2012-07-01	374.517
2012-10-01	381.264
2013-01-01	389.739
2013-04-01	401.291
2013-07-01	420.887
2013-10-01	434.633
2014-01-01	448.111
2014-04-01	462.369
2014-07-01	466.538
2014-10-01	502.347
2015-01-01	511.532
2015-04-01	530.783