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
2490
2489
2488
2487
2486
2485
2484
2483
2482
2481
2480
2479
2478
2477
2476
2475
2474
2473
2472
2471
2470