Year	%
2000	24.8
2001	24.6
2002	25
2003	25.5
2004	25.4
2005	24.6
2006	24.4
2007	22.8
2008	22.9
2009	21.6
2010	21.8
2011	21
2012	21
2013	20.6
2014	19.6
2015	19.8
2016	19.8
2017	19.5
2018	19.3
2019	19.4