Year	% of population
2001	10.4
2002	9.1
2003	8.6
2004	8.9
2005	9.3
2006	9.5
2007	9.2
2008	9.5
2009	7.2
2010	4.7
2011	2.5
2012	2.5
2013	2.5
2014	2.5
2015	2.6
2016	2.7
2017	2.8
2018	2.9
2019	3.3
2020	3.5
2021	4.2