Year	% of population
2001	21
2002	22.7
2003	22.7
2004	22.7
2005	22.3
2006	22.7
2007	22
2008	21.1
2009	15.8
2010	12
2011	8.1
2012	8.6
2013	8.7
2014	8.6
2015	9
2016	9.7
2017	10.8
2018	11.9
2019	13.4
2020	14.1
2021	13.9