Year	% of population
2001	12.9
2002	13
2003	12.9
2004	12.5
2005	12
2006	11.2
2007	10.4
2008	9.9
2009	9.3
2010	8.8
2011	8.3
2012	8.1
2013	7.9
2014	7.8
2015	7.8
2016	7.8
2017	7.7
2018	7.7
2019	8.2
2020	8.7
2021	9.2