Year Percent 2000 20.97092 2001 20.98235 2002 22.54134 2003 24.10033 2004 25.66624 2005 27.23919 2006 28.81227 2007 30.46653 2008 32.1287 2009 33.79896 2010 35.47747 2011 37.16457 2012 38.86031 2013 40.56485 2014 42.2784 2015 44.00131 2016 45.7336 2017 47.47762 2018 49.23414 2019 51.00348 2020 52.649 2021 54.29859 2022 55.95194