Year	%
2000	29.8
2001	28.6
2002	28
2003	27.3
2004	26.7
2005	26.1
2006	25.6
2007	25.3
2008	24.8
2009	24.5
2010	24.3
2011	24.1
2012	24
2013	23.9
2014	23.9
2015	23.7
2016	23.7
2017	23.7
2018	23.7
2019	23.8