Year	Number
1958	-9
1959	-9
1960	-9
1961	-9
1962	-9
1963	-9
1964	-9
1965	-9
1966	-9
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	-7
1985	-7
1986	-7
1987	-7
1988	-7
1989	-7
1990	-7
1991	-5
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	5
2011	5