Quarter	Billions of US Dollars
1989-10-01	0.641
1990-01-01	0.449
1990-04-01	0.234
1990-07-01	0.882
1990-10-01	1.262
1991-01-01	0.738
1991-04-01	1.591
1991-07-01	1.140
1991-10-01	0.941
1992-01-01	1.139
1992-04-01	1.789
1992-07-01	2.846
1992-10-01	2.644
1993-01-01	1.612
1993-04-01	1.684
1993-07-01	2.080
1993-10-01	2.226
1994-01-01	1.888
1994-04-01	2.088
1994-07-01	2.095
1994-10-01	2.114
1995-01-01	1.954
1995-04-01	1.875
1995-07-01	2.137
1995-10-01	2.138
1996-01-01	2.688
1996-04-01	2.879
1996-07-01	2.910
1996-10-01	2.792
1997-01-01	3.233
1997-04-01	3.540
1997-07-01	3.889
1997-10-01	3.676
1998-01-01	3.433
1998-04-01	3.068
1998-07-01	3.535
1998-10-01	3.259
1999-01-01	3.070
1999-04-01	3.281
1999-07-01	3.263
1999-10-01	3.298
2000-01-01	3.353
2000-04-01	4.253
2000-07-01	4.051
2000-10-01	3.858
2001-01-01	9.485
2001-04-01	10.401
2001-07-01	9.582
2001-10-01	6.395
2002-01-01	5.549
2002-04-01	6.437
2002-07-01	5.601
2002-10-01	7.155
2003-01-01	8.939
2003-04-01	9.848
2003-07-01	11.557
2003-10-01	11.296
2004-01-01	12.257
2004-04-01	12.127
2004-07-01	14.493
2004-10-01	18.807
2005-01-01	17.471
2005-04-01	17.519
2005-07-01	17.871
2005-10-01	17.390
2006-01-01	18.566
2006-04-01	16.036
2006-07-01	16.141
2006-10-01	18.478
2007-01-01	18.725
2007-04-01	20.412
2007-07-01	23.016
2007-10-01	23.250
2008-01-01	19.323
2008-04-01	22.332
2008-07-01	23.475
2008-10-01	21.899
2009-01-01	23.389
2009-04-01	30.004
2009-07-01	30.712
2009-10-01	30.788
2010-01-01	31.995
2010-04-01	32.917
2010-07-01	36.721
2010-10-01	37.977
2011-01-01	38.882
2011-04-01	39.456
2011-07-01	34.232
2011-10-01	33.720
2012-01-01	35.271
2012-04-01	33.218
2012-07-01	32.223
2012-10-01	29.771
2013-01-01	29.730
2013-04-01	28.136
2013-07-01	28.634
2013-10-01	26.175
2014-01-01	26.348
2014-04-01	26.566
2014-07-01	25.826
2014-10-01	25.896
2015-01-01	23.765