Year	%
2000	18.5
2001	15.8
2002	17
2003	16.4
2004	16.8
2005	17
2006	17.2
2007	16.2
2008	18.1
2009	16.4
2010	14.3
2011	12.9
2012	13
2013	13.1
2014	12.8
2015	13.2
2016	13.4
2017	13.6
2018	13.7
2019	13.8