Year Percent 2000 41.14431 2001 42.25468 2002 43.3768 2003 44.36387 2004 45.35133 2005 46.33602 2006 47.15023 2007 47.96147 2008 48.7704 2009 49.57516 2010 50.37684 2011 51.17484 2012 51.96854 2013 52.75735 2014 53.54151 2015 54.31693 2016 55.08427 2017 55.84291 2018 56.59175 2019 56.88304 2020 57.16774 2021 57.44673 2022 57.71956