Year Percent 2000 36.82795 2001 39.19106 2002 41.53751 2003 43.86641 2004 46.17847 2005 48.4726 2006 50.7498 2007 53.00935 2008 55.2522 2009 57.47693 2010 59.68185 2011 61.80066 2012 63.95307 2013 66.09924 2014 68.23888 2015 70.37171 2016 72.49693 2017 74.61426 2018 76.72373 2019 78.82496 2020 80.91815 2021 83.00309 2022 83.0453