Year	%
1986	13.8
1989	12.5
1992	12.3
1996	13.5
1997	13.3
2000	12.3
2001	12.7
2002	13
2003	12.1
2004	12
2005	12.6
2006	12
2007	12.9
2008	13
2009	12.8
2010	13.1
2011	12.9
2012	13.5
2013	13
2014	13.9
2015	13.8
2016	13.8
2017	14.4
2018	13.9
2019	14.4
2020	14.9
2021	15.2
2022	15.7