Year	%
2004	43.5
2005	45.5
2006	42.6
2007	44.1
2008	43.5
2009	42.6
2010	41.7
2011	42.8
2012	42.3
2013	42.6
2014	42.2
2015	41.5
2016	41.5
2017	42.4
2018	42.3
2019	42
2020	42.9
2021	41.5