Quarter	Billions of US Dollars
1990-01-01	0.134
1990-04-01	0.135
1990-07-01	0.138
1990-10-01	0.138
1991-01-01	0.230
1991-04-01	0.230
1991-07-01	0.210
1991-10-01	0.213
1995-07-01	0.279
1995-10-01	0.377
1996-01-01	0.396
1996-04-01	0.769
1996-07-01	0.597
1996-10-01	0.866
1997-01-01	2.648
1997-04-01	1.239
1997-07-01	0.257
1997-10-01	0.100
1998-01-01	0.098
1998-04-01	0.057
1999-07-01	0.366
1999-10-01	0.667
2000-01-01	0.344
2000-04-01	0.511
2000-07-01	1.491
2000-10-01	1.433
2001-01-01	1.251
2001-04-01	1.402
2001-07-01	2.375
2001-10-01	2.487
2002-01-01	3.059
2002-04-01	3.564
2002-07-01	3.438
2002-10-01	3.105
2003-01-01	3.456
2003-04-01	4.132
2003-07-01	6.548
2003-10-01	7.725
2004-01-01	8.489
2004-04-01	9.834
2004-07-01	10.549
2004-10-01	11.215
2005-01-01	17.249
2005-04-01	18.339
2005-07-01	18.151
2005-10-01	20.415
2006-01-01	24.715
2006-04-01	25.106
2006-07-01	26.604
2006-10-01	33.808
2007-01-01	38.813
2007-04-01	41.341
2007-07-01	41.213
2007-10-01	46.606
2008-01-01	53.701
2008-04-01	55.922
2008-07-01	50.478
2008-10-01	44.085
2009-01-01	50.732
2009-04-01	54.750
2009-07-01	53.596
2009-10-01	57.664
2010-01-01	65.253
2010-04-01	65.747
2010-07-01	75.554
2010-10-01	77.729
2011-01-01	81.560
2011-04-01	82.125
2011-07-01	88.222
2011-10-01	84.501
2012-01-01	89.385
2012-04-01	77.164
2012-07-01	67.342
2012-10-01	68.035
2013-01-01	72.083
2013-04-01	62.596
2013-07-01	58.585
2013-10-01	54.790
2014-01-01	59.516
2014-04-01	63.147
2014-07-01	59.913
2014-10-01	58.148
2015-01-01	67.072