Year	%
2004	13.5
2005	12.5
2006	13.8
2007	13.8
2008	13.9
2009	14.1
2010	13.4
2011	13.8
2012	13.3
2013	13
2014	13.2
2015	13.3
2016	13.2
2017	13.2
2018	13.5
2019	13.4
2020	13.4
2021	13.2