Y \ X
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
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
6470
6469
6468
6467
6466
6465
6464
6463
6462
6461
6460
6459
6458
6457
6456
6455
6454
6453
6452
6451
6450