Quarter	Billions of US Dollars
1993-07-01	12.750
1993-10-01	11.677
1994-01-01	20.036
1994-04-01	6.606
1994-07-01	9.430
1994-10-01	11.805
1995-01-01	7.654
1995-04-01	13.638
1995-07-01	17.444
1995-10-01	10.428
1996-01-01	22.370
1996-04-01	28.447
1996-07-01	34.772
1996-10-01	31.397
1997-01-01	31.588
1997-04-01	31.218
1997-07-01	39.379
1997-10-01	32.223
1998-01-01	33.626
1998-04-01	41.101
1998-07-01	31.716
1998-10-01	15.921
1999-01-01	42.048
1999-04-01	32.562
1999-07-01	33.107
1999-10-01	21.830
2000-01-01	38.959
2000-04-01	43.859
2000-07-01	32.112
2000-10-01	39.400
2001-01-01	46.649
2001-04-01	48.172
2001-07-01	38.629
2001-10-01	37.051
2002-01-01	42.419
2002-04-01	42.450
2002-07-01	41.414
2002-10-01	37.847
2003-01-01	65.826
2003-04-01	51.030
2003-07-01	58.053
2003-10-01	48.269
2004-01-01	89.929
2004-04-01	64.772
2004-07-01	44.722
2004-10-01	57.690
2005-01-01	54.172
2005-04-01	59.217
2005-07-01	62.185
2005-10-01	112.789
2006-01-01	88.470
2006-04-01	136.714
2006-07-01	122.691
2006-10-01	181.481
2007-01-01	160.391
2007-04-01	176.019
2007-07-01	75.748
2007-10-01	44.426
2008-01-01	84.218
2008-04-01	66.537
2008-07-01	60.403
2008-10-01	61.206
2009-01-01	86.034
2009-04-01	91.687
2009-07-01	55.159
2009-10-01	53.861
2010-01-01	60.129
2010-04-01	44.161
2010-07-01	37.839
2010-10-01	43.923
2011-01-01	71.803
2011-04-01	66.909
2011-07-01	39.239
2011-10-01	64.917
2012-01-01	53.307
2012-04-01	57.605
2012-07-01	46.558
2012-10-01	46.596
2013-01-01	77.562
2013-04-01	64.437
2013-07-01	88.101
2013-10-01	82.385
2014-01-01	77.441
2014-04-01	106.142
2014-07-01	64.133
2014-10-01	51.238
2015-01-01	70.362
2015-04-01	52.658