Year Percent 2000 4.16113 2001 4.64521 2002 5.13883 2003 5.64179 2004 6.54982 2005 7.66562 2006 8.79676 2007 9.94309 2008 11.10501 2009 12.28236 2010 13.47606 2011 14.68599 2012 15.91256 2013 17.1558 2014 18.41614 2015 19.69384 2016 20.9889 2017 22.30157 2018 23.6323 2019 24.98111 2020 26.34822 2021 27.73389 2022 27.84382