Quarter	Billions of US Dollars
1993-07-01	2.908
1993-10-01	3.277
1994-01-01	3.439
1994-04-01	2.788
1994-07-01	2.690
1994-10-01	3.814
1995-01-01	3.581
1995-04-01	3.554
1995-07-01	4.662
1995-10-01	5.257
1996-01-01	7.094
1996-04-01	6.572
1996-07-01	6.200
1996-10-01	6.904
1997-01-01	9.049
1997-04-01	8.636
1997-07-01	8.564
1997-10-01	10.583
1998-01-01	9.783
1998-04-01	10.629
1998-07-01	10.513
1998-10-01	11.143
1999-01-01	11.699
1999-04-01	15.542
1999-07-01	16.082
1999-10-01	15.661
2000-01-01	20.338
2000-04-01	19.977
2000-07-01	20.013
2000-10-01	21.178
2001-01-01	25.380
2001-04-01	27.634
2001-07-01	23.545
2001-10-01	24.829
2002-01-01	26.390
2002-04-01	32.765
2002-07-01	34.932
2002-10-01	33.557
2003-01-01	43.964
2003-04-01	46.840
2003-07-01	42.543
2003-10-01	48.389
2004-01-01	51.763
2004-04-01	53.797
2004-07-01	56.599
2004-10-01	70.025
2005-01-01	74.028
2005-04-01	83.401
2005-07-01	84.687
2005-10-01	88.479
2006-01-01	98.345
2006-04-01	95.891
2006-07-01	98.361
2006-10-01	102.205
2007-01-01	118.946
2007-04-01	118.173
2007-07-01	95.955
2007-10-01	90.275
2008-01-01	109.055
2008-04-01	97.748
2008-07-01	78.062
2008-10-01	97.396
2009-01-01	65.422
2009-04-01	67.155
2009-07-01	69.050
2009-10-01	65.147
2010-01-01	68.567
2010-04-01	56.505
2010-07-01	62.085
2010-10-01	67.322
2011-01-01	84.589
2011-04-01	87.877
2011-07-01	87.992
2011-10-01	95.682
2012-01-01	107.707
2012-04-01	86.654
2012-07-01	79.893
2012-10-01	66.698
2013-01-01	86.043
2013-04-01	84.219
2013-07-01	84.514
2013-10-01	80.700
2014-01-01	81.497
2014-04-01	84.933
2014-07-01	77.292
2014-10-01	82.265
2015-01-01	73.525
2015-04-01	70.677