Year	%
2000	17.6
2001	17
2002	16.1
2003	15.5
2004	15.1
2005	15
2006	14.3
2007	14.2
2008	13.3
2009	12.6
2010	12.8
2011	12.4
2012	12.1
2013	12.2
2014	11.6
2015	11.8
2016	11.3
2017	11.1
2018	11.2
2019	10.9