Year	%
2000	14.8
2001	15.2
2002	14.5
2003	15
2004	15.7
2005	16.4
2006	16.3
2007	15.5
2008	15.8
2009	16.3
2010	16.8
2011	16.7
2012	17.1
2013	17.1
2014	17.1
2015	17.4
2016	17.2
2017	16.3
2018	16.7
2019	16.5