Year Percent 2000 24.70019 2001 26.90676 2002 29.16171 2003 31.46505 2004 33.81679 2005 36.21691 2006 38.66543 2007 41.16234 2008 43.70764 2009 46.30133 2010 48.94341 2011 51.63388 2012 54.37274 2013 57.15999 2014 59.99563 2015 62.87967 2016 65.81209 2017 68.79291 2018 71.82211 2019 74.89971 2020 78.0257 2021 81.20008 2022 83.56946