Year	Number
1945	-5
1946	2
1947	2
1948	3
1949	3
1950	0
1951	0
1952	0
1953	0
1954	0
1955	0
1956	0
1957	-1
1958	-1
1959	-5
1960	-5
1961	-5
1962	-5
1963	-5
1964	-5
1965	-5
1966	-6
1967	-7
1968	-7
1969	-7
1970	-7
1971	-7
1972	-7
1973	-7
1974	-7
1975	-7
1976	-7
1977	-7
1978	-7
1979	-7
1980	-7
1981	-7
1982	-7
1983	-7
1984	-7
1985	-7
1986	-7
1987	-7
1988	-7
1989	-7
1990	-7
1991	-7
1992	-7
1993	-7
1994	-7
1995	-7
1996	-7
1997	-7
1998	-5
1999	6
2000	6
2001	6
2002	6
2003	6
2004	8
2005	8
2006	8
2007	8
2008	8
2009	8
2010	8
2011	8