Year	%
2000	27.3
2001	26.8
2002	26.9
2003	27.8
2004	27.6
2005	25.8
2006	23.6
2007	23.1
2008	23.6
2009	23.9
2010	24.6
2011	24.5
2012	25.7
2013	25.2
2014	25.9
2015	26.7
2016	27.3
2017	27.1
2018	26.4
2019	26.3