Year Percent 2000 70.50477 2001 71.07587 2002 71.64557 2003 72.21387 2004 72.78079 2005 74.44507 2006 76.12196 2007 77.81174 2008 79.51418 2009 81.22912 2010 82.96585 2011 84.71907 2012 86.48265 2013 88.25648 2014 90.04056 2015 91.83475 2016 93.63967 2017 95.45492 2018 96.99974 2019 97.86485 2020 98.49327 2021 98.49597 2022 98.49878