Year % of population 2006 29 2007 26.3 2008 23.7 2009 23.9 2010 24.8 2011 26.4 2012 26.8 2013 27.5 2014 27.2 2015 25.8 2016 24.5 2017 24.1 2018 21.3 2019 22.2 2020 21.5 2021 20.1