Quarter	Billions of US Dollars
1987-01-01	1.8099
1987-04-01	1.7211
1987-07-01	1.6436
1987-10-01	1.4715
1988-01-01	1.2953
1988-04-01	1.2975
1988-07-01	1.3984
1988-10-01	1.4312
1989-01-01	1.3619
1989-04-01	1.3001
1989-07-01	1.2925
1989-10-01	1.3139
1990-01-01	1.2705
1990-04-01	1.2843
1990-07-01	1.3235
1990-10-01	1.2133
1991-01-01	1.1548
1991-04-01	1.1446
1991-07-01	1.1781
1991-10-01	1.2218
1992-01-01	1.3029
1992-04-01	1.4818
1992-07-01	1.3925
1992-10-01	1.5957
1993-01-01	1.8170
1993-04-01	0.6819
1993-07-01	0.6113
1993-10-01	0.5799
1994-01-01	0.6104
1994-04-01	0.5392
1994-07-01	0.5549
1994-10-01	0.5607
1995-01-01	0.6131
1995-04-01	0.4714
1995-07-01	0.3405
1995-10-01	0.2465
1996-01-01	0.2505
1996-04-01	0.2364
1996-07-01	0.2440
1996-10-01	0.2487
1997-01-01	0.2303
1997-04-01	0.2458
1997-07-01	0.2677
1997-10-01	0.1797
1998-01-01	0.2666
1998-04-01	0.2334
1998-07-01	0.2143
1998-10-01	0.2160
1999-01-01	0.2059
1999-04-01	0.2122
1999-07-01	0.2225
1999-10-01	0.2137
2000-01-01	0.2022
2000-04-01	0.1974
2000-07-01	0.1829
2000-10-01	0.1767
2001-01-01	0.1683
2001-04-01	0.1684
2001-07-01	0.1525
2001-10-01	0.1153
2002-01-01	0.5734
2002-04-01	0.5875
2002-07-01	0.8149
2002-10-01	0.8447
2003-01-01	0.8607
2003-04-01	0.8708
2003-07-01	0.8894
2003-10-01	1.1001
2004-01-01	1.9112
2004-04-01	2.1670
2004-07-01	2.1626
2004-10-01	2.3850
2005-01-01	3.5867
2005-04-01	4.4743
2005-07-01	5.6832
2005-10-01	8.7940
2006-01-01	10.1700
2006-04-01	13.9151
2006-07-01	14.9700
2006-10-01	20.5291
2007-01-01	25.1442
2007-04-01	25.8718
2007-07-01	26.7718
2007-10-01	26.3746
2008-01-01	30.0732
2008-04-01	30.9829
2008-07-01	30.5125
2008-10-01	26.0329
2009-01-01	24.0820
2009-04-01	24.1313
2009-07-01	25.7037
2009-10-01	25.1480
2010-01-01	24.0254
2010-04-01	22.5463
2010-07-01	22.6939
2010-10-01	21.7950
2011-01-01	23.4071
2011-04-01	22.4132
2011-07-01	22.2960
2011-10-01	22.0757
2012-01-01	21.6985
2012-04-01	22.3540
2012-07-01	23.0155
2012-10-01	27.9462
2013-01-01	29.9378
2013-04-01	35.2525
2013-07-01	36.4459
2013-10-01	38.8891
2014-01-01	39.9907
2014-04-01	44.4495
2014-07-01	46.8432
2014-10-01	50.5250
2015-01-01	52.7872
2015-04-01	57.3028