Year	%
2000	16.9
2001	16.6
2002	16.1
2003	15.6
2004	15
2005	14.4
2006	13.9
2007	13.4
2008	12.9
2009	12.6
2010	12.3
2011	12.2
2012	12.2
2013	12.3
2014	12.3
2015	12.4
2016	12.3
2017	12.2
2018	12.1
2019	12