Year	% of population
2001	21.3
2002	20.6
2003	19
2004	17.2
2005	15.9
2006	15.1
2007	14.9
2008	14.5
2009	13.1
2010	10.8
2011	8.7
2012	7.8
2013	7.1
2014	6.3
2015	5.8
2016	5.7
2017	5.6
2018	5.4
2019	6.4
2020	7.1
2021	8