1931	38.6
1932	33.7
1933	33.8
1934	79.2
1935	58.6
1936	39.3
1937	33.2
1938	29.2
1939	46.7
1940	80
1941	40.2
1942	53.8
1943	26.9
1944	34.7
1945	72.6
1946	30.2
1947	54.5
1948	30
1949	30
1950	30
1951	76.2
1952	27.4
1953	69.4
1954	22.8
1955	34.8
1956	38.8
1957	39.8
1958	58.1
1959	58.1
1960	48.5
1961	66.5
1962	24.5
1963	64.1
1964	53.9
1965	66.5
1966	32.9
1967	52.4
1968	27.8
1969	27.3
1970	80
1971	50.4
1972	43.2
1973	39.6
1974	38.7
1975	40.2
1976	55.7
1977	118.9
1978	25
1979	55.6
1980	40.1
1981	89.4
1982	27.2
1983	32.7
1984	105.7
1985	25.3
1986	27.6
1987	128.5
1988	24.7