Quarter	Billions of US Dollars
1987-01-01	0.17264
1987-04-01	0.17105
1987-07-01	0.17005
1987-10-01	0.25039
1988-01-01	0.23383
1988-04-01	0.27824
1988-07-01	0.26423
1988-10-01	0.27926
1989-01-01	0.29819
1989-04-01	0.29588
1989-07-01	0.30593
1989-10-01	0.32008
1990-01-01	0.33077
1990-04-01	0.34921
1990-07-01	0.38106
1990-10-01	0.34350
1991-01-01	0.30479
1991-04-01	0.31731
1991-07-01	0.34150
1991-10-01	0.32091
1992-01-01	0.29029
1992-04-01	0.31579
1992-07-01	0.35380
1992-10-01	0.26442
1993-01-01	0.25753
1993-04-01	0.32130
1993-07-01	0.43527
1993-10-01	0.48462
1994-01-01	0.56525
1994-04-01	0.59279
1994-07-01	0.61975
1994-10-01	0.60770
1995-01-01	0.69968
1995-04-01	0.77932
1995-07-01	0.87166
1995-10-01	0.86658
1996-01-01	0.72425
1996-04-01	0.68877
1996-07-01	0.58079
1996-10-01	0.54219
1997-01-01	0.43412
1997-04-01	0.43186
1997-07-01	0.43388
1997-10-01	0.43290
1998-01-01	0.41417
1998-04-01	0.36106
1998-07-01	0.39645
1998-10-01	0.39956
1999-01-01	0.36982
1999-04-01	0.35427
1999-07-01	0.36728
1999-10-01	0.28132
2000-01-01	0.20973
2000-04-01	0.21521
2000-07-01	0.20162
2000-10-01	0.21387
2001-01-01	0.20211
2001-04-01	0.11140
2001-07-01	0.12409
2001-10-01	0.11924
2002-01-01	0.11884
2002-04-01	0.13557
2002-07-01	0.06742
2002-10-01	0.07211
2003-01-01	0.07387
2006-04-01	0.21900
2006-07-01	0.21536
2006-10-01	0.22126
2007-01-01	0.22109
2007-04-01	0.42394
2007-07-01	0.44444
2007-10-01	0.46202
2008-01-01	0.52319
2008-04-01	0.51096
2008-07-01	0.47200
2008-10-01	0.48886
2009-01-01	0.45678
2009-04-01	0.48135
2009-07-01	0.50534
2009-10-01	0.50461
2010-01-01	0.49047
2010-04-01	0.66593
2010-07-01	0.73998
2010-10-01	0.76628
2011-01-01	0.78706
2011-04-01	0.53931
2011-07-01	0.49922
2011-10-01	0.47827
2012-01-01	0.49828
2012-04-01	0.20934
2012-07-01	0.48103
2012-10-01	0.49094
2013-01-01	0.78773
2013-04-01	0.79686
2013-07-01	0.82855
2013-10-01	0.84128
2014-01-01	0.84842
2014-04-01	0.84241
2014-07-01	0.78280
2014-10-01	0.75827
2015-01-01	0.77097
2015-04-01	1.02085