Bang 3
Nam	T7	Nam	T7	Nam	T7	Nam	T7	Nam	T7
50
1941	29.5	1951	28.4	1961	29.5	1971	28.3	1981	29.0
1942	28.7	1952	28.7	1962	29.1	1972	28.3	1982	29.4
1943	28.4	1953	29.4	1963	28.6	1973	28.8	1983	30.4
1944	28.5	1954	30.4	1964	29.1	1974	28.8	1984	29.6
1945	29.4	1955	28.8	1965	29.0	1975	29.4	1985	29.1
1946	28.8	1956	28.3	1966	29.2	1976	29.3	1986	29.1
1947	29.1	1957	28.9	1967	29.6	1977	28.9	1987	29.5
1948	28.6	1958	28.7	1968	29.6	1978	29.1	1988	29.5
1949	28.5	1959	28.5	1969	29.2	1979	29.8	1989	29.1
1950	28.4	1960	27.9	1970	29.0	1980	28.8	1990	28.7