Year	%
2004	27.9
2005	27.2
2006	26.8
2007	26.8
2008	27.6
2009	27.6
2010	24.8
2011	24.5
2012	26.8
2013	27.1
2014	28.9
2015	28.6
2016	29.5
2017	28.4
2018	27.2
2019	27.5
2020	28.5
2021	29.1