Year	%
2000	16.5
2001	16.1
2002	15.3
2003	14.2
2004	13.5
2005	13.1
2006	12.5
2007	12.5
2008	12.5
2009	11.3
2010	11
2011	11
2012	10.7
2013	10.3
2014	9.8
2015	9.9
2016	9.7
2017	9.5
2018	9.3
2019	9.5