Year	%
2000	45.8
2001	48.1
2002	50.3
2003	52.2
2004	53.2
2005	53.5
2006	54
2007	55.7
2008	56.1
2009	55.9
2010	54.6
2011	53.1
2012	52.7
2013	51.2
2014	49
2015	47.6
2016	47
2017	46
2018	45.3
2019	45.2