Year	% of population
1982	16.9
1983	17.1
1984	17
1985	17
1986	17
1987	16.9
1988	16.9
1989	16.7
1990	16.9
1991	17.2
1992	17.5
1993	18.3
1994	18.5
1995	18.1
1996	18.2
1997	17.3
1998	17.4
1999	17.6
2000	17.3
2001	17.1
2002	17
2003	17
2004	16.8
2005	16.7
2006	16.6
2007	16.4
2008	16.3
2009	15.8
2010	15.3
2011	15.4
2012	15.6
2013	15.7
2014	15.4
2015	15.4
2016	15.4
2017	15.4
2018	15.1
2019	15.1
2020	14.5
2021	14
2022	14