Year Percent 2000 7.3192 2001 7.80248 2002 8.28576 2003 8.76904 2004 9.25232 2005 9.86258 2006 10.48545 2007 11.12092 2008 11.769 2009 12.42969 2010 13.10299 2011 13.78889 2012 14.4874 2013 15.19851 2014 15.92223 2015 16.65856 2016 17.4075 2017 18.16904 2018 18.94319 2019 19.72995 2020 20.52931 2021 21.11344 2022 21.69758