Quarter	Billions of US Dollars
1987-01-01	0.80814
1987-04-01	0.91903
1987-07-01	1.00118
1987-10-01	1.03997
1988-01-01	0.95627
1988-04-01	0.85654
1988-07-01	0.96651
1988-10-01	1.01219
1989-01-01	0.99697
1989-04-01	0.99783
1989-07-01	0.91656
1989-10-01	0.79289
1990-01-01	0.82608
1990-04-01	0.82525
1990-07-01	1.05185
1990-10-01	1.19338
1991-01-01	1.15007
1991-04-01	1.08245
1991-07-01	1.10396
1991-10-01	1.09281
1992-01-01	1.03308
1992-04-01	0.92856
1992-07-01	0.93840
1992-10-01	0.65465
1993-01-01	0.66574
1993-04-01	0.69562
1993-07-01	0.27500
1993-10-01	0.27500
1994-01-01	0.07500
1994-04-01	0.07500
1994-07-01	0.07500
1994-10-01	0.07500
1995-01-01	0.07500
1995-04-01	0.07500
1995-07-01	0.07500
1995-10-01	0.07500
1996-01-01	0.07500
1996-04-01	0.07500
1996-07-01	0.07500
1996-10-01	0.07500
1997-01-01	0.07500
1997-04-01	0.07500
2009-10-01	0.22423
2010-01-01	0.22898
2010-04-01	0.21307
2010-07-01	0.24167
2010-10-01	0.29569
2011-01-01	0.95909
2011-04-01	0.67057
2011-07-01	0.83799
2011-10-01	0.56401
2012-01-01	0.85183
2012-04-01	0.94903
2012-07-01	0.92981
2012-10-01	0.98703
2013-01-01	0.90562
2013-04-01	0.90967
2013-07-01	1.06715
2013-10-01	1.30111
2014-01-01	1.31474
2014-04-01	1.48475
2014-07-01	1.31405
2014-10-01	1.00304
2015-01-01	1.05688
2015-04-01	1.05081