Year	%
2000	15.8
2001	15.2
2002	14.4
2003	13.9
2004	13.4
2005	13.2
2006	13
2007	12.8
2008	12.4
2009	12.1
2010	11.8
2011	11.5
2012	11.1
2013	10.9
2014	10.8
2015	10.7
2016	10.6
2017	10.5
2018	10.5
2019	10.5