Year	% of population
2002	13.2
2003	13
2004	12.6
2005	12.6
2006	12
2007	15.2
2008	14.5
2009	14.7
2010	14.5
2011	14.4
2012	14.4
2013	14.1
2014	13.9
2015	14.1
2016	14.4
2017	14.3
2018	13.3
2019	13.9
2020	14.7
2021	14.8