回归分析论文
22.9 1915 21.4 1916 21.6 1917 21.6 1918 20.5 1919 22.7 1920 20.0 1921
20.3 1922
21.0 1923
22.1 1924
20.9 1925
21.8 1926
22.3 1927
21.7 1928
22.5 1929 21.2 1930 23.6 1931
20.5 1932
21.3 1933
22.2 1934 22.1 1935 19.4 1936 21.7 1937 21.1 1938
21.8 1939
22.2 1940 22.2 1941 21.4 1942
20.3 1943
21.8 1944 21.2 1945
20.7 1946
21.1 1947 21.8 1948 21.7 1949 21.6 1950
20.5 1951
21.7 1952
22.7 1953
21.4 1954
22.2 1955 22.0 1956 22.3 1957 21.7 1958