Year	%
1986	20.7
1990	21.4
1994	21.4
1998	21.5
2005	21.3
2006	21.4
2009	22.3
2011	22.5
2012	22.2
2013	22.2
2014	22.2
2015	22
2016	21.9
2017	22.1
2018	21.9
2019	22.1
2020	22.3
2021	22.5
2022	22.4