Year	%
1994	24
1995	23.3
1996	23.1
1997	22.7
1998	25
1999	23.7
2000	22.9
2003	23.5
2004	23.8
2005	22.8
2006	23.7
2007	23.8
2008	24.1
2009	24.7
2010	23.6
2011	23.7
2012	23.4
2013	24.3
2014	24.1
2015	23.8
2016	23.8
2017	23
2018	23.9
2019	23.2
2020	23.1
2021	23.8