Year	%
2000	23.1
2001	22.7
2002	22.3
2003	22.2
2004	22
2005	21.7
2006	21.4
2007	21.1
2008	20.7
2009	20.3
2010	19.9
2011	19.6
2012	19.3
2013	19
2014	19
2015	19
2016	19
2017	19
2018	19
2019	19.1