Year	%
2000	36.4
2001	37.8
2002	37.6
2003	38.7
2004	39.4
2005	39.6
2006	39.8
2007	40.3
2008	40
2009	39.4
2010	39.9
2011	39.9
2012	40.7
2013	40.5
2014	40.8
2015	40.8
2016	40.6
2017	40.2
2018	40.2
2019	40.3