Year	%
2000	28.6
2001	27.9
2002	27.2
2003	26.5
2004	25.8
2005	25.2
2006	24.7
2007	24.3
2008	23.9
2009	23.6
2010	23.2
2011	22.9
2012	22.9
2013	22.9
2014	23
2015	23
2016	23.2
2017	23.4
2018	23.7
2019	23.9