Year % (national estimate) 2006 37.39 2007 33.28 2008 32.469 2009 28.875 2010 28.206 2011 28.478 2012 29.631 2013 28.702 2014 28.46 2015 29.212 2016 30.31 2017 30.639 2018 30.002 2019 29.637 2020 28.297 2021 33.698 2022 32.711