Year	Number
1990	26
1991	25
1992	24
1993	23
1994	23
1995	22
1996	21
1997	20
1998	20
1999	20
2000	19
2001	19
2002	19
2003	20
2004	21
2005	21
2006	21
2007	20
2008	19
2009	18
2010	18
2011	16
2012	16
2013	16
2014	15
2015	14
2016	14
2017	14
2018	13
2019	13
2020	13
2021	14
2022	14