Year	%
2004	14.4
2005	13.9
2006	14.8
2007	15.1
2008	14.7
2009	14.4
2010	14.5
2011	14.5
2012	14.6
2013	14.1
2014	14.7
2015	14.6
2016	15.1
2017	15.4
2018	15
2019	15.4
2020	15
2021	15.2