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
2580
2579
2578
2577
2576
2575
2574
2573
2572
2571
2570
2569
2568
2567
2566
2565
2564
2563
2562
2561
2560