Year Percent 2000 28.01915 2001 29.20283 2002 30.38346 2003 31.56106 2004 32.73562 2005 33.90714 2006 35.07563 2007 36.24108 2008 37.4035 2009 38.56287 2010 39.71921 2011 40.87252 2012 42.02279 2013 43.17002 2014 44.31421 2015 45.45537 2016 46.59349 2017 47.72857 2018 48.86062 2019 49.98963 2020 51.11561 2021 51.11561 2022 51.11561