Quarter	Billions of US Dollars
1975-01-01	12.949
1975-04-01	13.343
1975-07-01	11.898
1975-10-01	12.640
1976-01-01	13.121
1976-04-01	13.561
1976-07-01	14.678
1976-10-01	15.566
1977-01-01	16.037
1977-04-01	16.403
1977-07-01	16.403
1977-10-01	18.311
1978-01-01	18.314
1978-04-01	18.573
1978-07-01	20.038
1978-10-01	21.231
1979-01-01	21.458
1979-04-01	22.068
1979-07-01	23.815
1979-10-01	24.346
1980-01-01	23.645
1980-04-01	26.359
1980-07-01	27.010
1980-10-01	26.385
1981-01-01	26.796
1981-04-01	24.567
1981-07-01	25.424
1981-10-01	27.132
1982-01-01	26.517
1982-04-01	26.870
1982-07-01	24.899
1982-10-01	25.640
1983-01-01	25.855
1983-04-01	26.634
1983-07-01	27.006
1983-10-01	26.938
1984-01-01	28.700
1984-04-01	28.056
1984-07-01	26.474
1984-10-01	26.864
1985-01-01	28.326
1985-04-01	30.069
1985-07-01	34.876
1985-10-01	39.828
1986-01-01	43.379
1986-04-01	44.622
1986-07-01	47.159
1986-10-01	49.413
1987-01-01	55.619
1987-04-01	58.979
1987-07-01	61.459
1987-10-01	70.461
1988-01-01	71.375
1988-04-01	69.259
1988-07-01	67.425
1988-10-01	73.221
1989-01-01	69.263
1989-04-01	67.885
1989-07-01	71.185
1989-10-01	77.080
1990-01-01	77.334
1990-04-01	79.830
1990-07-01	84.802
1990-10-01	89.509
1991-01-01	78.596
1991-04-01	74.065
1991-07-01	79.752
1991-10-01	87.585
1992-01-01	80.477
1992-04-01	86.286
1992-07-01	89.310
1992-10-01	74.908
1993-01-01	74.364
1993-04-01	71.471
1993-07-01	71.509
1993-10-01	68.283
1994-01-01	70.100
1994-04-01	73.677
1994-07-01	76.314
1994-10-01	77.345
1995-01-01	84.163
1995-04-01	85.359
1995-07-01	85.011
1995-10-01	84.285
1996-01-01	84.220
1996-04-01	84.168
1996-07-01	85.611
1996-10-01	88.205
1997-01-01	86.759
1997-04-01	80.209
1997-07-01	84.557
1997-10-01	83.430
1998-01-01	81.988
1998-04-01	83.366
1998-07-01	87.460
1998-10-01	86.155
1999-01-01	85.175
1999-04-01	85.964
1999-07-01	89.091
1999-10-01	88.407
2000-01-01	85.788
2000-04-01	87.698
2000-07-01	84.270
2000-10-01	89.456
2001-01-01	88.774
2001-04-01	89.827
2001-07-01	96.530
2001-10-01	97.797
2002-01-01	101.952
2002-04-01	124.648
2002-07-01	128.039
2002-10-01	140.347
2003-01-01	137.112
2003-04-01	140.532
2003-07-01	149.528
2003-10-01	162.388
2004-01-01	160.701
2004-04-01	164.748
2004-07-01	174.316
2004-10-01	199.979
2005-01-01	195.891
2005-04-01	196.162
2005-07-01	202.377
2005-10-01	202.584
2006-01-01	214.206
2006-04-01	233.558
2006-07-01	231.202
2006-10-01	248.653
2007-01-01	260.332
2007-04-01	277.607
2007-07-01	309.429
2007-10-01	320.991
2008-01-01	346.520
2008-04-01	355.622
2008-07-01	315.360
2008-10-01	266.380
2009-01-01	282.449
2009-04-01	301.227
2009-07-01	338.035
2009-10-01	343.756
2010-01-01	336.546
2010-04-01	313.896
2010-07-01	357.180
2010-10-01	363.692
2011-01-01	390.214
2011-04-01	407.841
2011-07-01	383.206
2011-10-01	380.352
2012-01-01	408.036
2012-04-01	396.514
2012-07-01	423.114
2012-10-01	441.521
2013-01-01	424.770
2013-04-01	422.066
2013-07-01	430.773
2013-10-01	434.470
2014-01-01	445.368
2014-04-01	440.974
2014-07-01	427.484
2014-10-01	376.415
2015-01-01	351.184
2015-04-01	367.997
2015-07-01	345.052
2015-10-01	336.570
2016-01-01	362.724
2016-04-01	365.027
2016-07-01	386.280
2016-10-01	365.411
2017-01-01	372.558
2017-04-01	388.086
2017-07-01	414.587
2017-10-01	408.426
2018-01-01	432.341