Quarter	Billions of US Dollars
1987-01-01	2.206
1987-04-01	2.233
1987-07-01	2.332
1987-10-01	2.518
1988-01-01	2.535
1988-04-01	2.893
1988-07-01	3.556
1988-10-01	3.821
1989-01-01	3.979
1989-04-01	3.377
1989-07-01	4.029
1989-10-01	4.460
1990-01-01	5.334
1990-04-01	6.294
1990-07-01	8.064
1990-10-01	7.669
1991-01-01	7.194
1991-04-01	7.722
1991-07-01	8.516
1991-10-01	9.409
1992-01-01	9.256
1992-04-01	10.389
1992-07-01	10.863
1992-10-01	10.152
1993-01-01	9.579
1993-04-01	13.015
1993-07-01	22.311
1993-10-01	24.331
1994-01-01	27.640
1994-04-01	29.793
1994-07-01	31.485
1994-10-01	33.230
1995-01-01	36.477
1995-04-01	37.127
1995-07-01	38.611
1995-10-01	39.588
1996-01-01	44.120
1996-04-01	46.930
1996-07-01	48.716
1996-10-01	54.280
1997-01-01	52.516
1997-04-01	52.960
1997-07-01	54.487
1997-10-01	54.959
1998-01-01	60.870
1998-04-01	64.732
1998-07-01	70.532
1998-10-01	70.287
1999-01-01	75.335
1999-04-01	79.867
1999-07-01	87.865
1999-10-01	88.432
2000-01-01	92.176
2000-04-01	98.204
2000-07-01	96.801
2000-10-01	103.955
2001-01-01	107.370
2001-04-01	104.999
2001-07-01	110.289
2001-10-01	112.437
2002-01-01	112.965
2002-04-01	133.841
2002-07-01	132.038
2002-10-01	141.866
2003-01-01	157.797
2003-04-01	171.213
2003-07-01	177.101
2003-10-01	203.516
2004-01-01	195.249
2004-04-01	188.447
2004-07-01	186.110
2004-10-01	207.118
2005-01-01	207.144
2005-04-01	211.509
2005-07-01	213.334
2005-10-01	241.692
2006-01-01	287.172
2006-04-01	321.865
2006-07-01	339.563
2006-10-01	355.747
2007-01-01	395.658
2007-04-01	415.665
2007-07-01	454.119
2007-10-01	466.535
2008-01-01	492.233
2008-04-01	519.773
2008-07-01	500.882
2008-10-01	454.150
2009-01-01	443.052
2009-04-01	471.961
2009-07-01	477.150
2009-10-01	465.101
2010-01-01	434.266
2010-04-01	380.557
2010-07-01	443.079
2010-10-01	421.404
2011-01-01	439.960
2011-04-01	441.132
2011-07-01	395.629
2011-10-01	366.755
2012-01-01	404.989
2012-04-01	362.564
2012-07-01	362.472
2012-10-01	350.589
2013-01-01	329.728
2013-04-01	320.409
2013-07-01	303.550
2013-10-01	311.038
2014-01-01	306.360
2014-04-01	310.716
2014-07-01	289.919
2014-10-01	271.963
2015-01-01	256.667
2015-04-01	256.490