Year Percent 1991 46.273 1992 46.307 1993 46.599 1994 45.595 1995 45.88 1996 45.751 1997 45.236 1998 44.942 1999 45.159 2000 44.562 2001 45.594 2002 46.756 2003 46.535 2004 46.481 2005 46.169 2006 45.332 2007 45.108 2008 44.761 2009 44.996 2010 45.365 2011 45.44 2012 45.325 2013 45.189 2014 45.083 2015 45.511 2016 45.14 2017 45.044 2018 45.04 2019 45.025 2020 44.913 2021 44.594 2022 44.214