Year	%
2004	24.3
2005	24.9
2006	26
2007	25.5
2008	26.2
2009	26.2
2010	25.7
2011	26.7
2012	28
2013	30.9
2014	28.8
2015	27.5
2016	26.8
2017	25.5
2018	27.2
2019	25.5
2020	26.3
2021	25.7