Year	% of population
1984	75.5
1985	71.9
1986	69.2
1987	65.6
1988	60.3
1989	68.7
1990	67.2
1991	65.4
1992	62.7
1993	59.9
1994	55.3
1995	52.4
1996	50
1997	49.8
1998	51
1999	48.4
2000	47
2001	45.6
2002	43.5
2003	41.6
2004	40
2005	38.1
2006	37.7
2007	36.6
2008	36.1
2009	35
2010	33.9
2011	32.1
2012	31.3
2013	28.2
2014	27.3
2015	26.1
2016	25.5
2017	25.2
2018	24.3
2019	23.3
2020	22.3
2021	21.6
2022	21.2