Year	Number
1990	25
1991	25
1992	25
1993	25
1994	26
1995	26
1996	26
1997	26
1998	27
1999	27
2000	27
2001	26
2002	26
2003	26
2004	26
2005	25
2006	25
2007	25
2008	25
2009	25
2010	27
2011	28
2012	28
2013	28
2014	28
2015	28
2016	28
2017	28
2018	28
2019	28
2020	29
2021	29
2022	29