Year	%
1982	28.6
1992	26.4
2000	25.9
2002	24.1
2006	26
2007	26.7
2008	26.3
2009	25.7
2010	25.4
2011	24.7
2012	25
2013	25.5
2014	25.5
2015	25.2
2016	25.8
2017	25.5
2018	25.8
2019	26.6
2020	26.4