Year	%
2000	12.9
2001	12.6
2002	12.3
2003	11.8
2004	11.5
2005	11.4
2006	10.9
2007	10.6
2008	10.5
2009	10.1
2010	9.9
2011	9.8
2012	9.3
2013	9.3
2014	9.3
2015	9.3
2016	9
2017	8.7
2018	8.7
2019	8.6