Year Percent 2000 47.84253 2001 48.34402 2002 48.84735 2003 49.35253 2004 49.85955 2005 50.36841 2006 50.87911 2007 51.39165 2008 51.90603 2009 52.42226 2010 52.94032 2011 53.46023 2012 53.98198 2013 54.50557 2014 55.031 2015 55.55827 2016 56.08738 2017 56.61833 2018 57.15113 2019 57.68577 2020 57.68577 2021 57.68577 2022 57.68577