Year	%
2000	43.7
2001	43.6
2002	43.5
2003	43.4
2004	43.1
2005	42.8
2006	42.3
2007	41.7
2008	41.1
2009	40.4
2010	39.9
2011	39.5
2012	39.3
2013	39.1
2014	39.1
2015	39
2016	39.1
2017	39.2
2018	39.2
2019	39.3