Year Percent 2002 50.62385 2003 52.14647 2004 53.66761 2005 55.17522 2006 56.68125 2007 58.18566 2008 59.68904 2009 61.70332 2010 63.73992 2011 65.79894 2012 67.8794 2013 69.98087 2014 72.10317 2015 74.24583 2016 76.40837 2017 78.59012 2018 80.79101 2019 82.38412 2020 83.97422 2021 85.56091 2022 87.01864