Year	%
1997	25.2
1998	25.2
2000	30
2001	30
2002	30
2003	30
2004	34.8
2005	34.8
2006	34.8
2007	34.8
2008	34.8
2009	39.2
2010	39.2
2011	39.2
2012	39.2
2013	39.2
2015	39.6
2016	39.6
2017	39.6
2018	39.6
2019	41.2
2020	42.4
2021	42.4
2022	42.4
2023	43.2