Quarter	Billions of US Dollars
1987-01-01	0.03984
1987-04-01	0.03947
1987-07-01	0.03924
1987-10-01	0.04695
1988-01-01	0.04384
1988-04-01	0.03975
1988-07-01	0.03775
1988-10-01	0.06489
1989-01-01	0.09514
1989-04-01	0.08686
1989-07-01	0.06208
1989-10-01	0.06580
1990-01-01	0.08909
1990-04-01	0.12433
1990-07-01	0.14319
1990-10-01	0.09831
1991-10-01	0.01000
1992-01-01	0.01000
1992-04-01	0.01000
1992-07-01	0.01000
1992-10-01	0.01000
1993-01-01	0.01000
1993-04-01	0.01000
1993-07-01	0.01000
1993-10-01	0.18500
1994-01-01	0.34000
1994-04-01	0.40058
1994-07-01	0.40094
1994-10-01	0.46622
1995-01-01	0.48142
1995-04-01	0.50019
1995-07-01	0.52852
1995-10-01	0.92811
1996-01-01	1.14422
1996-04-01	1.15054
1996-07-01	1.88957
1996-10-01	2.19225
1997-01-01	2.58358
1997-04-01	2.69220
1997-07-01	2.68387
1997-10-01	2.67392
1998-01-01	2.67031
1998-04-01	2.66388
1998-07-01	2.67297
1998-10-01	2.60668
1999-01-01	2.59976
1999-04-01	2.54781
1999-07-01	2.54953
1999-10-01	2.49500
2000-01-01	2.49500
2000-04-01	2.49500
2000-07-01	2.49500
2000-10-01	2.39500
2001-01-01	2.32000
2001-04-01	2.32000
2001-07-01	1.77000
2001-10-01	1.57000
2002-01-01	1.57000
2002-04-01	1.45000
2002-07-01	1.45000
2002-10-01	1.45000
2003-01-01	1.45000
2003-04-01	1.45000
2003-07-01	1.45000
2003-10-01	1.45000
2004-01-01	1.30000
2004-04-01	1.30000
2004-07-01	1.54910
2004-10-01	1.55565
2005-01-01	1.95247
2005-04-01	2.10964
2005-07-01	1.80722
2005-10-01	1.80324
2006-01-01	1.80370
2006-04-01	2.12569
2006-07-01	2.42338
2006-10-01	2.49183
2007-01-01	2.19499
2007-04-01	2.19174
2007-07-01	2.19832
2007-10-01	2.20063
2008-01-01	2.36936
2008-04-01	2.35805
2008-07-01	2.35899
2008-10-01	2.37285
2009-01-01	2.36259
2009-04-01	2.36822
2009-07-01	2.10460
2009-10-01	2.10503
2010-01-01	1.85734
2010-04-01	1.52097
2010-07-01	1.52613
2010-10-01	1.67672
2011-01-01	1.67632
2011-04-01	1.53131
2011-07-01	1.23021
2011-10-01	1.22889
2012-01-01	1.23106
2012-04-01	1.22855
2012-07-01	1.23109
2012-10-01	1.23162
2013-01-01	1.08530
2013-04-01	1.20532
2013-07-01	1.20464
2013-10-01	1.20119
2014-01-01	1.20206
2014-04-01	1.20203
2014-07-01	1.20222
2014-10-01	1.10084
2015-01-01	1.14948
2015-04-01	1.14579