Year Percent 2000 96.39745 2001 96.46936 2002 96.54127 2003 96.61316 2004 96.68505 2005 96.75693 2006 96.8288 2007 96.90067 2008 96.97252 2009 97.04437 2010 97.11621 2011 97.18804 2012 97.25987 2013 97.33168 2014 97.40349 2015 97.47529 2016 97.54708 2017 97.61887 2018 97.69064 2019 97.76241 2020 97.83417 2021 97.90593 2022 97.97767