Year Percent 2000 53.54882 2001 53.6563 2002 53.76378 2003 53.87126 2004 53.97873 2005 54.08621 2006 55.84549 2007 57.61131 2008 59.38369 2009 61.16262 2010 62.9481 2011 64.74013 2012 66.53872 2013 68.34385 2014 70.15554 2015 71.97378 2016 73.79858 2017 75.62992 2018 77.46781 2019 79.31226 2020 79.4656 2021 79.61894 2022 79.61894