Year	% of population
2001	22.4
2002	21.6
2003	22
2004	22.5
2005	22.6
2006	22.1
2007	21.2
2008	21
2009	18.6
2010	16.4
2011	14.1
2012	14.3
2013	15.1
2014	15.6
2015	15.5
2016	14.9
2017	14.3
2018	14.1
2019	14.5
2020	16.2
2021	18.7