Year	%
2000	27
2001	28.3
2002	28.9
2003	29.5
2004	29.3
2005	29
2006	29.4
2007	29.1
2008	29.4
2009	29.9
2010	29.9
2011	29.2
2012	30
2013	28.8
2014	29.2
2015	30.4
2016	29.4
2017	28.1
2018	28.3
2019	28
