Year Percent 2000 82.84719 2001 83.13201 2002 83.42087 2003 83.70987 2004 83.99888 2005 84.28778 2006 84.57683 2007 84.86577 2008 85.15485 2009 85.44394 2010 85.73292 2011 86.02204 2012 86.31118 2013 86.6024 2014 86.89574 2015 87.19113 2016 87.48839 2017 87.78755 2018 88.08866 2019 88.39141 2020 88.69595 2021 89.00221 2022 89.31011