Year	%
2000	14.4
2001	14
2002	13.8
2003	13.5
2004	13.1
2005	12.7
2006	12.3
2007	12.2
2008	11.9
2009	11.5
2010	11.1
2011	10.8
2012	10.7
2013	10.5
2014	10.4
2015	10.3
2016	10.4
2017	10.1
2018	9.8
2019	9.6