Year Percent 2000 55.03691 2001 56.55064 2002 58.06437 2003 59.57809 2004 61.09182 2005 62.7054 2006 64.3238 2007 65.94703 2008 67.57509 2009 69.20798 2010 70.84569 2011 72.48824 2012 74.13561 2013 75.78781 2014 77.44484 2015 79.10669 2016 80.77338 2017 82.44489 2018 84.12123 2019 85.8024 2020 87.4884 2021 89.17923 2022 90.65111