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
4410
4409
4408
4407
4406
4405
4404
4403
4402
4401
4400
4399
4398
4397
4396
4395
4394
4393
4392
4391
4390