Year Percent 2000 53.85515 2001 54.69444 2002 55.5307 2003 56.36428 2004 57.19482 2005 58.02267 2006 58.84746 2007 59.66952 2008 60.48852 2009 61.30794 2010 62.12746 2011 62.94703 2012 63.76602 2013 64.58462 2014 65.40196 2015 66.21843 2016 67.03293 2017 67.84582 2018 68.65666 2019 69.46488 2020 70.27047 2021 71.07283 2022 71.87191