Year	%
2000	45
2001	44.6
2002	44.2
2003	43.6
2004	43.1
2005	42.5
2006	42
2007	41.4
2008	40.9
2009	40.5
2010	40.2
2011	40.2
2012	40.4
2013	40.7
2014	41.2
2015	41.8
2016	42.4
2017	43
2018	43.6
2019	44.2