Year	Number
1948	10
1949	10
1950	10
1951	10
1952	10
1953	10
1954	10
1955	10
1956	10
1957	10
1958	10
1959	10
1960	10
1961	10
1962	10
1963	10
1964	10
1965	10
1966	10
1967	9
1968	9
1969	9
1970	9
1971	9
1972	9
1973	9
1974	9
1975	9
1976	9
1977	9
1978	9
1979	9
1980	9
1981	9
1982	9
1983	9
1984	9
1985	9
1986	9
1987	9
1988	9
1989	9
1990	9
1991	9
1992	9
1993	9
1994	9
1995	9
1996	9
1997	9
1998	9
1999	10
2000	10
2001	10
2002	10
2003	10
2004	10
2005	10
2006	10
2007	10
2008	10
2009	10
2010	10
2011	10