1908	13.72	1936	15.21	1964	16.85
1912	14.43	1940	15.72	1968	17.39
1916	14.33	1944	16.00	1972	17.35
1920	14.92	1948	15.40	1976	17.29
1924	14.76	1952	16.22	1980	17.35
1928	14.50	1956	16.34	1984	17.56
1932	15.53	1960	16.81	1988	17.61