Year Percent 2000 40.51997 2001 42.05354 2002 43.59885 2003 45.15592 2004 46.72473 2005 48.30529 2006 49.8976 2007 51.50166 2008 53.11747 2009 54.74502 2010 56.38433 2011 58.03538 2012 59.69818 2013 61.37273 2014 63.05902 2015 64.75707 2016 66.46686 2017 68.1884 2018 69.92169 2019 71.66673 2020 73.42351 2021 75.19205 2022 76.97233