Year	%
2000	31.4
2001	32.7
2002	32.6
2003	33.8
2004	34.6
2005	35
2006	35.2
2007	35.7
2008	35.5
2009	34.9
2010	35.4
2011	35.4
2012	36.2
2013	36.1
2014	36.4
2015	36.4
2016	36.3
2017	35.9
2018	35.9
2019	36