Y \ X
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
8940
8939
8938
8937
8936
8935
8934
8933
8932
8931
8930
8929
8928
8927
8926
8925
8924
8923
8922
8921
8920