Year % of adults 2004 0 2005 1 2006 5.5 2007 10.9 2008 24.7 2009 30.2 2010 33.3 2011 42 2012 44.9 2013 46.9 2014 46.6 2015 50.1 2016 51.1 2017 54.8 2018 55.7 2019 54.5