Year	%
2006	45
2007	43.3
2008	42.3
2009	41.5
2010	41.1
2011	41.2
2012	41.8
2013	41.6
2014	40.7
2015	40.8
2016	39.6
2017	41
2018	41.2
2019	40.4
2020	40
2021	39.9