Year Percent 2006 87.71006 2007 88.14973 2008 88.59048 2009 89.0323 2010 89.47519 2011 89.91915 2012 90.36418 2013 90.81028 2014 91.25746 2015 91.7057 2016 92.15502 2017 92.60541 2018 93.05687 2019 93.5094 2020 93.91034 2021 93.91034 2022 93.91034