Year	% of population
1999	16
2000	16
2001	15.6
2002	16.6
2004	20.5
2005	19.1
2006	17.3
2007	16.9
2008	17.1
2009	17.6
2010	17.7
2011	17.1
2012	17.3
2013	17
2014	17.6
2015	17.3
2016	15
2017	14.8
2018	15.4
2019	14.8
2020	11.8
2021	12.2
2022	11.8