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
15450
15449
15448
15447
15446
15445
15444
15443
15442
15441
15440
15439
15438
15437
15436
15435
15434
15433
15432
15431
15430