Quarter	Billions of US Dollars
1987-01-01	0.981
1987-04-01	1.275
1987-07-01	1.395
1987-10-01	1.536
1988-01-01	1.690
1988-04-01	1.720
1988-07-01	2.055
1988-10-01	2.158
1989-01-01	2.742
1989-04-01	2.996
1989-07-01	3.212
1989-10-01	4.554
1990-01-01	5.389
1990-04-01	6.078
1990-07-01	6.942
1990-10-01	8.100
1991-01-01	8.956
1991-04-01	10.256
1991-07-01	11.764
1991-10-01	14.556
1992-01-01	15.933
1992-04-01	18.353
1992-07-01	19.669
1992-10-01	18.727
1993-01-01	19.554
1993-04-01	19.964
1993-07-01	27.324
1993-10-01	28.617
1994-01-01	30.220
1994-04-01	31.238
1994-07-01	34.006
1994-10-01	35.132
1995-01-01	38.778
1995-04-01	41.065
1995-07-01	43.207
1995-10-01	46.786
1996-01-01	48.241
1996-04-01	49.813
1996-07-01	52.404
1996-10-01	55.261
1997-01-01	55.131
1997-04-01	56.398
1997-07-01	59.361
1997-10-01	58.339
1998-01-01	59.987
1998-04-01	60.967
1998-07-01	63.640
1998-10-01	64.484
1999-01-01	63.785
1999-04-01	63.307
1999-07-01	67.520
1999-10-01	67.397
2000-01-01	68.688
2000-04-01	71.921
2000-07-01	67.119
2000-10-01	72.234
2001-01-01	72.674
2001-04-01	72.961
2001-07-01	76.250
2001-10-01	71.995
2002-01-01	72.900
2002-04-01	84.608
2002-07-01	85.273
2002-10-01	89.284
2003-01-01	99.436
2003-04-01	103.778
2003-07-01	105.416
2003-10-01	116.502
2004-01-01	117.830
2004-04-01	111.380
2004-07-01	122.324
2004-10-01	136.133
2005-01-01	130.044
2005-04-01	127.595
2005-07-01	133.057
2005-10-01	131.879
2006-01-01	145.683
2006-04-01	152.197
2006-07-01	155.006
2006-10-01	174.247
2007-01-01	188.780
2007-04-01	195.495
2007-07-01	206.492
2007-10-01	222.675
2008-01-01	239.191
2008-04-01	251.211
2008-07-01	225.510
2008-10-01	207.984
2009-01-01	212.143
2009-04-01	231.203
2009-07-01	240.319
2009-10-01	234.794
2010-01-01	239.338
2010-04-01	225.311
2010-07-01	247.444
2010-10-01	237.817
2011-01-01	241.166
2011-04-01	241.263
2011-07-01	219.174
2011-10-01	198.058
2012-01-01	192.785
2012-04-01	177.066
2012-07-01	180.688
2012-10-01	179.139
2013-01-01	155.296
2013-04-01	147.426
2013-07-01	157.077
2013-10-01	190.319
2014-01-01	165.216
2014-04-01	155.241
2014-07-01	146.241
2014-10-01	143.940
2015-01-01	142.702
2015-04-01	145.133