Year	Number
1960	-8
1961	-8
1962	-9
1963	-9
1964	-9
1965	-9
1966	-7
1967	-7
1968	-7
1969	-2
1970	3
1971	3
1972	-7
1973	-7
1974	-7
1975	-7
1976	-7
1977	-7
1978	0
1979	6
1980	6
1981	-7
1982	-7
1983	-7
1984	-7
1985	-7
1986	-7
1987	-7
1988	-7
1989	-7
1990	-7
1991	-4
1992	-1
1993	-1
1994	-1
1995	-1
1996	2
1997	2
1998	2
1999	2
2000	2
2001	6
2002	6
2003	6
2004	8
2005	8
2006	8
2007	8
2008	8
2009	8
2010	8
2011	8