Year Percent 2000 8.73437 2001 10.35184 2002 11.95965 2003 13.55779 2004 15.14626 2005 16.72506 2006 18.29419 2007 19.85366 2008 21.40346 2009 22.94359 2010 24.47406 2011 25.99485 2012 27.50598 2013 29.00745 2014 30.49924 2015 31.98136 2016 33.45382 2017 34.91661 2018 36.36974 2019 37.81319 2020 39.24698 2021 40.6711 2022 42.21752