Year % of population 2001 16.6 2002 15.6 2003 15.4 2004 14.7 2005 13.6 2006 12.1 2007 10.7 2008 9.6 2009 7.8 2010 6.3 2011 5 2012 4.6 2013 4.4 2014 4.3 2015 4.2 2016 3.8 2017 3.9 2018 4.3 2019 6.6 2020 9.7 2021 12.8