Year	% of population
2001	46.7
2002	44.1
2003	42.5
2004	39.1
2005	37.1
2006	35.6
2007	35
2008	33.5
2009	28.2
2010	24.2
2011	20.3
2012	18.9
2013	17.3
2014	15.6
2015	14.5
2016	14.1
2017	15.5
2018	18
2019	20.7
2020	22.3
2021	21.9