Year % of adults 2004 7.9 2005 9.8 2006 9.1 2007 11.3 2008 11.3 2009 16.4 2010 16.3 2011 21.5 2012 22.9 2013 23.2 2014 23.4 2015 16.1 2016 7.8 2017 7.8 2018 7.9 2019 7.9