Year Percent 2000 1.91478 2001 2.31825 2002 2.72173 2003 3.1252 2004 3.52867 2005 3.89152 2006 4.24603 2007 4.5922 2008 4.93003 2009 5.25953 2010 5.58069 2011 5.89352 2012 6.19801 2013 6.49416 2014 6.78197 2015 7.06145 2016 7.33259 2017 7.59539 2018 7.84985 2019 8.09598 2020 8.33377 2021 8.67055 2022 9.00733