Year	Number
1902	3
1903	3
1904	3
1905	3
1906	3
1907	3
1908	3
1909	3
1910	3
1911	3
1912	3
1913	3
1914	3
1915	3
1916	3
1917	3
1918	3
1919	3
1920	3
1921	3
1922	3
1923	3
1924	3
1925	3
1926	3
1927	3
1928	1
1929	1
1930	1
1931	1
1932	1
1933	3
1934	3
1935	3
1936	3
1937	3
1938	3
1939	3
1940	3
1941	3
1942	3
1943	3
1944	3
1945	3
1946	3
1947	3
1948	3
1949	3
1950	3
1951	3
1952	0
1953	-3
1954	-6
1955	-9
1956	-9
1957	-9
1958	-9
1959	0
1960	-4
1961	-7
1962	-7
1963	-7
1964	-7
1965	-7
1966	-7
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	-7
1999	-7
2000	-7
2001	-7
2002	-7
2003	-7
2004	-7
2005	-7
2006	-7
2007	-7
2008	-7
2009	-7
2010	-7
2011	-7