Year	% of population
2001	50.4
2002	49.5
2003	49
2004	48.5
2005	46.5
2006	43.5
2007	41.5
2008	40.1
2009	33.5
2010	26.7
2011	21.1
2012	21.4
2013	22.7
2014	22.6
2015	23.7
2016	24.2
2017	25.7
2018	26.8
2019	27.5
2020	27.3
2021	27.8