Quarter	Billions of US Dollars
1993-07-01	19.398
1993-10-01	23.483
1994-01-01	16.264
1994-04-01	51.399
1994-07-01	20.482
1994-10-01	17.213
1995-01-01	16.868
1995-04-01	13.913
1995-07-01	11.087
1995-10-01	13.698
1996-01-01	19.621
1996-04-01	26.381
1996-07-01	32.061
1996-10-01	36.370
1997-01-01	38.451
1997-04-01	54.078
1997-07-01	53.563
1997-10-01	8.811
1998-01-01	60.928
1998-04-01	68.217
1998-07-01	25.177
1998-10-01	15.894
1999-01-01	64.293
1999-04-01	74.843
1999-07-01	61.824
1999-10-01	25.503
2000-01-01	61.802
2000-04-01	47.003
2000-07-01	112.553
2000-10-01	76.254
2001-01-01	156.665
2001-04-01	128.074
2001-07-01	77.707
2001-10-01	113.197
2002-01-01	113.414
2002-04-01	103.365
2002-07-01	25.800
2002-10-01	55.671
2003-01-01	19.564
2003-04-01	54.078
2003-07-01	93.869
2003-10-01	75.354
2004-01-01	70.455
2004-04-01	2.151
2004-07-01	52.496
2004-10-01	51.747
2005-01-01	59.121
2005-04-01	35.576
2005-07-01	55.511
2005-10-01	68.408
2006-01-01	36.980
2006-04-01	49.051
2006-07-01	83.658
2006-10-01	102.058
2007-01-01	62.348
2007-04-01	131.888
2007-07-01	78.520
2007-10-01	69.038
2008-01-01	-8.923
2008-04-01	132.288
2008-07-01	6.139
2008-10-01	-41.886
2009-01-01	86.353
2009-04-01	135.353
2009-07-01	102.776
2009-10-01	155.676
2010-01-01	118.759
2010-04-01	49.354
2010-07-01	131.302
2010-10-01	113.662
2011-01-01	115.845
2011-04-01	74.077
2011-07-01	63.360
2011-10-01	51.200
2012-01-01	182.610
2012-04-01	107.279
2012-07-01	155.631
2012-10-01	184.309
2013-01-01	141.629
2013-04-01	166.844
2013-07-01	48.561
2013-10-01	135.413
2014-01-01	127.697
2014-04-01	157.384
2014-07-01	156.033
2014-10-01	108.088
2015-01-01	146.267
2015-04-01	194.086