Year	% of population
2001	38
2002	34.7
2003	34
2004	35
2005	34.3
2006	32.7
2007	31.3
2008	28.6
2009	29
2010	30.3
2011	33
2012	33
2013	33.1
2014	33
2015	32.6
2016	31.5
2017	31.4
2018	31.8
2019	32.7
2020	32.4
2021	31.6