Quarter	Billions of US Dollars
1987-01-01	6.566
1987-04-01	7.073
1987-07-01	7.208
1987-10-01	7.846
1988-01-01	8.679
1988-04-01	9.497
1988-07-01	9.705
1988-10-01	10.833
1989-01-01	11.705
1989-04-01	11.663
1989-07-01	12.168
1989-10-01	13.506
1990-01-01	14.241
1990-04-01	14.882
1990-07-01	16.721
1990-10-01	17.504
1991-01-01	17.983
1991-04-01	18.912
1991-07-01	19.667
1991-10-01	22.170
1992-01-01	21.425
1992-04-01	24.039
1992-07-01	25.346
1992-10-01	23.324
1993-01-01	20.799
1993-04-01	20.347
1993-07-01	27.210
1993-10-01	28.898
1994-01-01	30.550
1994-04-01	33.434
1994-07-01	35.857
1994-10-01	37.043
1995-01-01	38.188
1995-04-01	39.311
1995-07-01	43.224
1995-10-01	45.883
1996-01-01	46.697
1996-04-01	48.886
1996-07-01	50.279
1996-10-01	52.680
1997-01-01	53.349
1997-04-01	57.368
1997-07-01	58.377
1997-10-01	61.233
1998-01-01	61.798
1998-04-01	64.832
1998-07-01	66.533
1998-10-01	68.674
1999-01-01	68.437
1999-04-01	72.643
1999-07-01	80.505
1999-10-01	80.455
2000-01-01	83.043
2000-04-01	90.759
2000-07-01	90.489
2000-10-01	99.249
2001-01-01	101.273
2001-04-01	98.324
2001-07-01	110.836
2001-10-01	115.410
2002-01-01	113.215
2002-04-01	128.188
2002-07-01	124.107
2002-10-01	124.832
2003-01-01	122.971
2003-04-01	130.048
2003-07-01	129.839
2003-10-01	149.697
2004-01-01	149.299
2004-04-01	159.960
2004-07-01	176.384
2004-10-01	206.740
2005-01-01	214.083
2005-04-01	214.656
2005-07-01	208.085
2005-10-01	221.160
2006-01-01	243.706
2006-04-01	278.537
2006-07-01	288.638
2006-10-01	324.866
2007-01-01	350.400
2007-04-01	378.846
2007-07-01	405.491
2007-10-01	440.023
2008-01-01	497.001
2008-04-01	537.862
2008-07-01	496.538
2008-10-01	493.268
2009-01-01	481.569
2009-04-01	511.488
2009-07-01	534.254
2009-10-01	524.923
2010-01-01	487.711
2010-04-01	434.085
2010-07-01	512.706
2010-10-01	490.693
2011-01-01	541.234
2011-04-01	565.045
2011-07-01	527.316
2011-10-01	502.733
2012-01-01	507.357
2012-04-01	456.393
2012-07-01	461.938
2012-10-01	467.488
2013-01-01	435.952
2013-04-01	443.175
2013-07-01	457.978
2013-10-01	465.066
2014-01-01	454.698
2014-04-01	441.221
2014-07-01	382.532
2014-10-01	363.790
2015-01-01	322.977
2015-04-01	330.820