Year Percent 2000 6.18379 2001 7.30952 2002 8.45013 2003 9.60563 2004 10.77601 2005 11.96128 2006 13.16143 2007 14.37648 2008 15.6064 2009 16.85121 2010 18.11091 2011 19.3855 2012 20.67496 2013 21.97932 2014 23.29856 2015 24.63269 2016 25.9817 2017 27.3456 2018 28.72438 2019 30.11805 2020 31.5266 2021 31.5266 2022 31.5266