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
2880
2879
2878
2877
2876
2875
2874
2873
2872
2871
2870
2869
2868
2867
2866
2865
2864
2863
2862
2861
2860