Year	%
2000	26.6
2001	26.2
2002	26
2003	25.7
2004	25.8
2005	25.2
2006	25.2
2007	25.4
2008	25.6
2009	25.8
2010	25.6
2011	25.3
2012	24.7
2013	25.2
2014	24.9
2015	24
2016	24
2017	23.8
2018	23.2
2019	23
