Quarter	Billions of US Dollars
1987-01-01	2.1535
1987-04-01	2.3114
1987-07-01	2.2309
1987-10-01	2.3304
1988-01-01	2.6981
1988-04-01	2.8737
1988-07-01	2.9141
1988-10-01	3.0736
1989-01-01	3.0452
1989-04-01	3.1113
1989-07-01	3.2850
1989-10-01	3.3836
1990-01-01	3.2128
1990-04-01	3.1745
1990-07-01	3.3021
1990-10-01	3.4025
1991-01-01	3.6414
1991-04-01	3.5323
1991-07-01	3.7838
1991-10-01	3.6906
1992-01-01	3.7260
1992-04-01	3.6855
1992-07-01	3.7809
1992-10-01	3.3194
1993-01-01	3.5369
1993-04-01	3.4798
1993-07-01	4.0174
1993-10-01	3.5811
1994-01-01	4.1099
1994-04-01	4.3760
1994-07-01	4.4316
1994-10-01	3.7776
1995-01-01	4.1445
1995-04-01	4.0442
1995-07-01	4.4055
1995-10-01	4.3139
1996-01-01	5.0182
1996-04-01	4.8195
1996-07-01	4.9540
1996-10-01	4.5011
1997-01-01	6.1636
1997-04-01	7.1525
1997-07-01	7.0389
1997-10-01	5.7938
1998-01-01	7.0427
1998-04-01	7.7255
1998-07-01	8.3891
1998-10-01	7.6269
1999-01-01	7.6526
1999-04-01	7.6857
1999-07-01	7.6373
1999-10-01	6.9648
2000-01-01	8.1562
2000-04-01	8.9544
2000-07-01	8.5619
2000-10-01	7.9979
2001-01-01	8.2900
2001-04-01	9.1126
2001-07-01	8.9377
2001-10-01	8.0127
2002-01-01	8.6033
2002-04-01	10.0954
2002-07-01	9.5590
2002-10-01	10.4090
2003-01-01	11.2205
2003-04-01	12.5984
2003-07-01	12.3746
2003-10-01	13.7285
2004-01-01	13.7186
2004-04-01	14.8884
2004-07-01	14.8985
2004-10-01	16.5963
2005-01-01	16.6269
2005-04-01	17.0185
2005-07-01	17.5889
2005-10-01	18.0072
2006-01-01	18.8534
2006-04-01	21.1334
2006-07-01	21.6097
2006-10-01	23.3594
2007-01-01	25.4877
2007-04-01	26.1459
2007-07-01	31.2849
2007-10-01	31.8031
2008-01-01	35.2912
2008-04-01	38.2615
2008-07-01	37.5409
2008-10-01	36.1027
2009-01-01	34.2698
2009-04-01	33.9940
2009-07-01	33.7268
2009-10-01	34.8723
2010-01-01	35.5876
2010-04-01	33.6568
2010-07-01	34.5487
2010-10-01	34.4646
2011-01-01	35.7220
2011-04-01	35.7165
2011-07-01	35.3225
2011-10-01	34.0731
2012-01-01	31.2008
2012-04-01	29.8709
2012-07-01	29.9683
2012-10-01	29.4817
2013-01-01	26.9759
2013-04-01	21.7846
2013-07-01	21.6586
2013-10-01	20.8203
2014-01-01	20.1202
2014-04-01	20.0652
2014-07-01	20.9885
2014-10-01	18.3539
2015-01-01	17.1110
2015-04-01	16.8999