Year Percent 1990 0.97479 1991 0.95118 1992 0.93002 1993 0.94888 1994 0.91438 1995 1.29616 1996 1.18707 1997 0.99542 1998 1.1097 1999 1.10445 2000 1.1971 2001 1.14951 2002 1.15698 2003 1.16307 2004 1.11809 2005 1.10372 2006 1.09728 2007 1.07382 2008 1.06582 2009 1.05913 2010 1.0636 2011 1.16107 2012 1.10089 2013 1.13147 2014 1.12797 2015 1.13067 2016 1.13801 2017 1.14325 2018 1.13064 2019 1.13886 2020 1.13165