Year Percent 2000 69.60512 2001 70.08136 2002 70.55839 2003 71.0362 2004 71.51479 2005 71.99416 2006 72.47431 2007 72.95525 2008 73.43697 2009 73.91948 2010 74.40276 2011 74.88683 2012 75.37168 2013 75.85731 2014 76.34373 2015 76.83092 2016 77.3189 2017 77.80766 2018 78.29721 2019 78.78754 2020 79.27865 2021 79.77054 2022 80.26321