Year Ratio 1993-01-01 0.99771 1994-01-01 1.00100 1995-01-01 1.00256 1996-01-01 1.00157 1997-01-01 1.00189 1998-01-01 0.99902 1999-01-01 0.99386 2000-01-01 0.99046 2001-01-01 0.98891 2002-01-01 0.98652 2003-01-01 0.98504 2004-01-01 0.98312 2005-01-01 0.98303 2006-01-01 0.97774 2007-01-01 0.97724 2008-01-01 0.97738 2009-01-01 0.97876 2010-01-01 0.97600 2011-01-01 0.97097 2012-01-01 0.97940 2013-01-01 0.98684