Year Percent 2000 13.12939 2001 14.06694 2002 15.00448 2003 15.94203 2004 16.87957 2005 18.02441 2006 19.19106 2007 20.37953 2008 21.58981 2009 22.82191 2010 24.07583 2011 25.35156 2012 26.6491 2013 27.96847 2014 29.30964 2015 30.67263 2016 32.05744 2017 33.46407 2018 34.89251 2019 36.34276 2020 37.81483 2021 39.30872 2022 39.30872