Year	Number
1800	-6
1801	-6
1802	-6
1803	-6
1804	-6
1805	-6
1806	-6
1807	-6
1808	-6
1809	-6
1810	-6
1811	-6
1812	-6
1813	-6
1814	-6
1815	-6
1816	-6
1817	-6
1818	-6
1819	-6
1820	-6
1821	-6
1822	-6
1823	-6
1824	-6
1825	-6
1826	-6
1827	-6
1828	-6
1829	-6
1830	-6
1831	-6
1832	-6
1833	-6
1834	-6
1835	-6
1836	-6
1837	-6
1838	-6
1839	-6
1840	-6
1841	-6
1842	-6
1843	-6
1844	-6
1845	-6
1846	-6
1847	-6
1848	-6
1849	-6
1850	-6
1851	-6
1852	-6
1853	-6
1854	-6
1855	-6
1856	-6
1857	-6
1858	-6
1859	-6
1860	-6
1861	-6
1862	-6
1863	-6
1864	-6
1865	-6
1866	-6
1867	-6
1868	-6
1869	-6
1870	-6
1871	-6
1872	-6
1873	-6
1874	-6
1875	-6
1876	-6
1877	-6
1878	-6
1879	-6
1880	-6
1881	-6
1882	-6
1883	-6
1884	-6
1885	-6
1886	-6
1887	-6
1888	-6
1889	-6
1890	-6
1891	-6
1892	-6
1893	-6
1894	-6
1895	-6
1896	-6
1897	-6
1898	-6
1899	-6
1900	-6
1901	-6
1902	-6
1903	-6
1904	-6
1905	-6
1906	-6
1907	-6
1908	-6
1909	-6
1910	-6
1911	-6
1912	-6
1956	-5
1957	-5
1958	-5
1959	-5
1960	-5
1961	-4
1962	-4
1963	-3
1964	-3
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	-8
1978	-8
1979	-8
1980	-8
1981	-8
1982	-8
1983	-8
1984	-8
1985	-8
1986	-8
1987	-8
1988	-8
1989	-8
1990	-8
1991	-8
1992	-7
1993	-7
1994	-7
1995	-7
1996	-7
1997	-7
1998	-6
1999	-6
2000	-6
2001	-6
2002	-6
2003	-6
2004	-6
2005	-6
2006	-6
2007	-6
2008	-6
2009	-6
2010	-6
2011	-4