Year Percent 2000 56.50623 2001 57.77506 2002 59.05006 2003 60.33123 2004 61.61817 2005 62.91171 2006 64.21142 2007 65.5173 2008 66.82935 2009 68.14758 2010 69.47197 2011 70.80222 2012 72.14546 2013 73.49981 2014 74.8649 2015 76.23949 2016 77.62286 2017 79.01396 2018 80.41159 2019 81.81511 2020 81.85242 2021 81.89408 2022 81.93991