Year	Number
1963	2
1964	2
1965	2
1966	0
1967	0
1968	0
1969	-7
1970	-7
1971	-7
1972	-7
1973	-7
1974	-7
1975	-7
1976	-7
1977	-7
1978	-7
1979	-6
1980	-6
1981	-6
1982	-7
1983	-7
1984	-7
1985	-7
1986	-7
1987	-7
1988	-7
1989	-7
1990	-7
1991	-5
1992	-5
1993	-5
1994	-5
1995	-5
1996	-5
1997	-2
1998	-2
1999	-2
2000	-2
2001	-2
2002	8
2003	8
2004	8
2005	8
2006	8
2007	7
2008	7
2009	7
2010	8
2011	8