Year	%
2000	25.5
2001	25.5
2002	25.6
2003	25.8
2004	25.6
2005	25.8
2006	26.1
2007	26.2
2008	26.2
2009	26
2010	25.7
2011	25
2012	24.3
2013	23.8
2014	23.3
2015	22.9
2016	22.3
2017	21.8
2018	21.3
2019	20.9