Year Percent 2000 9.35119 2001 9.35303 2002 9.35481 2003 9.3567 2004 9.35854 2005 11.64302 2006 13.91952 2007 16.18819 2008 18.44887 2009 20.703 2010 22.95022 2011 25.19025 2012 27.4226 2013 29.64706 2014 31.86306 2015 34.0704 2016 36.26849 2017 38.45707 2018 40.63567 2019 42.80384 2020 44.96115 2021 47.10713 2022 49.24129