Quarter	Billions of US Dollars
1987-01-01	22.390
1987-04-01	24.673
1987-07-01	26.686
1987-10-01	29.465
1988-01-01	30.168
1988-04-01	29.844
1988-07-01	31.642
1988-10-01	33.729
1989-01-01	37.111
1989-04-01	40.211
1989-07-01	41.761
1989-10-01	43.628
1990-01-01	46.510
1990-04-01	46.944
1990-07-01	54.491
1990-10-01	54.282
1991-01-01	56.284
1991-04-01	54.505
1991-07-01	54.939
1991-10-01	55.352
1992-01-01	53.380
1992-04-01	53.973
1992-07-01	54.571
1992-10-01	52.936
1993-01-01	52.164
1993-04-01	50.695
1993-07-01	51.382
1993-10-01	50.124
1994-01-01	50.192
1994-04-01	50.180
1994-07-01	53.069
1994-10-01	55.950
1995-01-01	62.134
1995-04-01	68.822
1995-07-01	65.704
1995-10-01	66.399
1996-01-01	66.943
1996-04-01	69.586
1996-07-01	75.338
1996-10-01	77.993
1997-01-01	81.174
1997-04-01	84.583
1997-07-01	88.444
1997-10-01	86.582
1998-01-01	86.334
1998-04-01	80.701
1998-07-01	86.958
1998-10-01	93.087
1999-01-01	91.649
1999-04-01	92.251
1999-07-01	99.302
1999-10-01	102.604
2000-01-01	100.923
2000-04-01	102.115
2000-07-01	99.996
2000-10-01	95.753
2001-01-01	88.829
2001-04-01	90.993
2001-07-01	90.233
2001-10-01	85.042
2002-01-01	77.982
2002-04-01	84.790
2002-07-01	79.846
2002-10-01	71.922
2003-01-01	70.039
2003-04-01	70.903
2003-07-01	74.284
2003-10-01	76.155
2004-01-01	75.539
2004-04-01	75.302
2004-07-01	78.057
2004-10-01	81.978
2005-01-01	81.823
2005-04-01	77.005
2005-07-01	79.775
2005-10-01	78.687
2006-01-01	86.572
2006-04-01	89.734
2006-07-01	96.138
2006-10-01	99.547
2007-01-01	103.130
2007-04-01	107.632
2007-07-01	110.775
2007-10-01	114.837
2008-01-01	126.708
2008-04-01	125.401
2008-07-01	116.692
2008-10-01	120.895
2009-01-01	114.736
2009-04-01	119.130
2009-07-01	127.079
2009-10-01	124.974
2010-01-01	126.714
2010-04-01	118.445
2010-07-01	133.181
2010-10-01	136.290
2011-01-01	142.063
2011-04-01	142.991
2011-07-01	146.816
2011-10-01	143.790
2012-01-01	162.355
2012-04-01	160.409
2012-07-01	166.318
2012-10-01	163.010
2013-01-01	164.654
2013-04-01	166.293
2013-07-01	179.149
2013-10-01	183.531
2014-01-01	185.345
2014-04-01	200.248
2014-07-01	204.195
2014-10-01	197.942
2015-01-01	198.823
2015-04-01	201.679