Quarter Billions of US Dollars 1997-04-01 0.3440 1997-07-01 0.3398 1997-10-01 0.3348 1998-01-01 0.3249 1998-04-01 0.3317 1998-07-01 0.3580 1998-10-01 0.3586 1999-01-01 0.3295 1999-04-01 0.3168 1999-07-01 0.3272 1999-10-01 0.3082 2000-01-01 0.2931 2000-04-01 0.2932 2000-07-01 0.2689 2000-10-01 0.5646 2001-01-01 0.6684 2001-04-01 1.1505 2001-07-01 1.2389 2001-10-01 1.1957 2002-01-01 1.1837 2002-04-01 1.7456 2002-07-01 1.7255 2002-10-01 1.8352 2003-01-01 1.9066 2003-04-01 1.9997 2003-07-01 2.8547 2003-10-01 2.9049 2004-01-01 2.8115 2004-04-01 2.7956 2004-07-01 2.8541 2004-10-01 3.1328 2005-01-01 2.9817 2005-04-01 3.3858 2005-07-01 3.3718 2005-10-01 2.9493 2006-01-01 3.0260 2006-04-01 3.1783 2006-07-01 3.1650 2006-10-01 3.2925 2007-01-01 3.3295 2007-04-01 3.3763 2007-07-01 3.5448 2007-10-01 3.6802 2008-01-01 3.9530 2008-04-01 4.1775 2008-07-01 3.7903 2008-10-01 3.6880 2009-01-01 3.5266 2009-04-01 3.7455 2009-07-01 3.8804 2009-10-01 3.8176 2010-01-01 4.9198 2010-04-01 4.4789 2010-07-01 4.0262 2010-10-01 3.9418 2011-01-01 4.1911 2011-04-01 6.4316 2011-07-01 6.0088 2011-10-01 5.7579 2012-01-01 9.1988 2012-04-01 7.9767 2012-07-01 9.0739 2012-10-01 11.1718 2013-01-01 12.4384 2013-04-01 12.6034 2013-07-01 14.8842 2013-10-01 16.4777 2014-01-01 18.4752 2014-04-01 20.0719 2014-07-01 19.0238 2014-10-01 20.4140 2015-01-01 17.7834 2015-04-01 17.6647