Year	Number
1961	-6
1962	-6
1963	-6
1964	-6
1965	-6
1966	-6
1967	-6
1968	-6
1969	-6
1970	-6
1971	-6
1972	-6
1973	-6
1974	-6
1975	-6
1976	-6
1977	-6
1978	-6
1979	-6
1980	-6
1981	-6
1982	-6
1983	-6
1984	-6
1985	-6
1986	-6
1987	-6
1988	-6
1989	-6
1990	-6
1991	-6
1992	-5
1993	-5
1994	-5
1995	-1
1996	-1
1997	-1
1998	-1
1999	-1
2000	-1
2001	-1
2002	-1
2003	-1
2004	-1
2005	-1
2006	-1
2007	-1
2008	-1
2009	-1
2010	-1
2011	-1