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
13550
13549
13548
13547
13546
13545
13544
13543
13542
13541
13540
13539
13538
13537
13536
13535
13534
13533
13532
13531
13530