Year	%
2000	17.7
2001	16.7
2002	15.7
2003	15.4
2004	14.5
2005	13.9
2006	13.4
2007	13
2008	13
2009	12.8
2010	11.3
2011	11.9
2012	11.6
2013	11.4
2014	10.9
2015	10.6
2016	10.4
2017	10.2
2018	9.9
2019	9.7