Year	%
2000	25
2001	25
2002	24.8
2003	24.7
2004	24.4
2005	24.2
2006	23.9
2007	23.6
2008	23.2
2009	23
2010	22.8
2011	22.8
2012	22.8
2013	22.8
2014	22.9
2015	23.1
2016	23.2
2017	23.3
2018	23.4
2019	23.5