Year % of adults 2004 1.9 2005 2.2 2006 3.1 2007 2.9 2008 8.7 2009 14.3 2010 18.6 2011 29.4 2012 33.6 2013 39 2014 44.5 2015 50.3 2016 57.2 2017 35 2018 46.5 2019 48.7