Year	%
2000	24.6
2001	24.7
2002	24.7
2003	24.9
2004	24.6
2005	24.4
2006	24.3
2007	24.6
2008	24.5
2009	24.6
2010	24.7
2011	24.7
2012	24.6
2013	24.3
2014	24
2015	23.6
2016	23.4
2017	23.4
2018	23.2
2019	22.7
