Year Percent 2000 18.01044 2001 18.01044 2002 18.24271 2003 18.47499 2004 20.18315 2005 21.92796 2006 23.70942 2007 25.52754 2008 27.3823 2009 29.27371 2010 31.20177 2011 33.16648 2012 35.16785 2013 37.20586 2014 39.28052 2015 41.39184 2016 43.5398 2017 45.72441 2018 45.72441 2019 45.72441 2020 45.72441 2021 45.72441