Year	%
1979	14
1986	14.4
1991	14.4
1995	14.3
2000	14
2003	14
2004	13.3
2005	13.5
2006	14.4
2007	14.1
2008	14.2
2009	14.4
2010	14.5
2011	14.4
2012	14.4
2013	14.2
2014	14.2
2015	14.1
2016	14
2017	14.3
2018	14.1
2019	14.1