Quarter	Billions of US Dollars
1987-01-01	6.130
1987-04-01	6.632
1987-07-01	5.020
1987-10-01	1.146
1988-01-01	6.437
1988-04-01	9.166
1988-07-01	6.067
1988-10-01	9.236
1989-01-01	7.120
1989-04-01	6.335
1989-07-01	5.047
1989-10-01	8.629
1990-01-01	5.533
1990-04-01	6.274
1990-07-01	9.713
1990-10-01	7.803
1991-01-01	5.099
1991-04-01	9.467
1991-07-01	6.780
1991-10-01	4.501
1992-01-01	8.190
1992-04-01	4.313
1992-07-01	5.039
1992-10-01	2.190
1993-01-01	5.577
1993-04-01	8.563
1993-07-01	32.893
1993-10-01	11.887
1994-01-01	16.580
1994-04-01	14.298
1994-07-01	12.897
1994-10-01	5.785
1995-01-01	13.482
1995-04-01	13.235
1995-07-01	28.008
1995-10-01	22.770
1996-01-01	33.917
1996-04-01	33.940
1996-07-01	27.488
1996-10-01	39.567
1997-01-01	40.954
1997-04-01	34.261
1997-07-01	33.170
1997-10-01	24.404
1998-01-01	49.946
1998-04-01	62.684
1998-07-01	39.438
1998-10-01	30.440
1999-01-01	84.478
1999-04-01	108.150
1999-07-01	99.223
1999-10-01	51.726
2000-01-01	72.343
2000-04-01	86.602
2000-07-01	105.900
2000-10-01	133.723
2001-01-01	160.913
2001-04-01	139.307
2001-07-01	92.550
2001-10-01	158.989
2002-01-01	131.480
2002-04-01	134.812
2002-07-01	84.995
2002-10-01	91.297
2003-01-01	104.589
2003-04-01	102.229
2003-07-01	128.476
2003-10-01	153.799
2004-01-01	111.210
2004-04-01	123.973
2004-07-01	106.884
2004-10-01	129.400
2005-01-01	86.854
2005-04-01	141.825
2005-07-01	55.561
2005-10-01	188.305
2006-01-01	113.689
2006-04-01	227.744
2006-07-01	193.299
2006-10-01	282.292
2007-01-01	224.210
2007-04-01	322.533
2007-07-01	33.500
2007-10-01	99.692
2008-01-01	57.635
2008-04-01	255.596
2008-07-01	113.987
2008-10-01	330.851
2009-01-01	276.599
2009-04-01	178.895
2009-07-01	128.536
2009-10-01	107.896
2010-01-01	8.902
2010-04-01	-24.911
2010-07-01	28.439
2010-10-01	13.341
2011-01-01	-45.123
2011-04-01	-21.955
2011-07-01	13.712
2011-10-01	108.504
2012-01-01	92.111
2012-04-01	-86.848
2012-07-01	20.157
2012-10-01	67.745
2013-01-01	9.953
2013-04-01	8.921
2013-07-01	-3.922
2013-10-01	-15.989
2014-01-01	-34.918
2014-04-01	49.246
2014-07-01	7.618
2014-10-01	-26.428
2015-01-01	60.135
2015-04-01	82.601