Year	% of population
2001	36.9
2002	35.4
2003	34.3
2004	34.4
2005	33.8
2006	33
2007	30.5
2008	29.2
2009	23.9
2010	19.7
2011	16
2012	17.2
2013	23.5
2014	31.2
2015	39.5
2016	40.7
2017	35.5
2018	29.5
2019	27
2020	29.5
2021	30.5