Year	%
2000	35.5
2001	34.1
2002	33
2003	32
2004	31.4
2005	30.6
2006	29.6
2007	28.4
2008	27.5
2009	26.9
2010	26.4
2011	26
2012	25.5
2013	25.1
2014	24.7
2015	24.3
2016	23.8
2017	23.5
2018	23.4
2019	23.2