Year % of adults 2004 0.1 2005 2.3 2006 1.4 2007 2.4 2008 2.4 2009 3 2010 2.9 2011 8.2 2012 8.3 2013 9 2014 9.4 2015 10.9 2016 12.2 2017 11.9 2018 12.4 2019 13.2