Year % of adults 2004 0.1 2005 1.2 2006 1.1 2007 1.4 2008 1.2 2009 2.1 2010 2 2011 2.2 2012 2.4 2013 3.1 2014 2.6 2015 3.3 2016 3.1 2017 3.3 2018 4.6 2019 5.1