Years


DecadeNumber of problems
1280-1289 1
1300-1309 5
1350-1359 6
1490-1499 8
1510-1519 1
1600-1609 6
1730-1739 8
1750-1759 3
1760-1769 8
1780-1789 1
1800-1809 5
1810-1819 2
1820-1829 7
1830-1839 33
1840-1849 680
1850-1859 1,418
1860-1869 904
1870-1879 2,815
1880-1889 4,182
1890-1899 5,448
1900-1909 7,514
1910-1919 8,813
1920-1929 10,211
1930-1939 12,052
1940-1949 10,568
1950-1959 12,788
1960-1969 12,056
1970-1979 12,139
1980-1989 15,484
1990-1999 18,560
2000-2009 14,247
2010-2019 4,529

YearNumber of problems
1283 1
1300 5
1350 6
1497 8
1512 1
1600 5
1604 1
1737 8
1750 3
1763 3
1766 1
1769 4
1787 1
1800 1
1802 1
1806 3
1813 1
1814 1
1821 1
1822 1
1823 1
1826 3
1829 1
1830 1
1832 4
1835 1
1836 2
1837 23
1838 2
1840 1
1841 18
1842 85
1843 26
1844 69
1845 34
1846 56
1847 152
1848 103
1849 136
1850 80
1851 66
1852 100
1853 107
1854 92
1855 97
1856 153
1857 195
1858 282
1859 246
1860 200
1861 168
1862 95
1863 41
1864 46
1865 41
1866 48
1867 96
1868 104
1869 65
1870 140
1871 172
1872 191
1873 375
1874 424
1875 294
1876 323
1877 318
1878 328
1879 250
1880 455
1881 478
1882 368
1883 395
1884 359
1885 395
1886 474
1887 356
1888 521
1889 381
1890 473
1891 384
1892 460
1893 501
1894 543
1895 564
1896 631
1897 738
1898 636
1899 518
1900 646
1901 745
1902 698
1903 622
1904 731
1905 678
1906 804
1907 871
1908 874
1909 845
1910 737
1911 1,058
1912 780
1913 843
1914 711
1915 784
1916 883
1917 935
1918 1,055
1919 1,027
1920 1,022
1921 1,098
1922 929
1923 762
1924 831
1925 1,064
1926 1,106
1927 1,003
1928 1,152
1929 1,244
1930 1,316
1931 1,135
1932 1,223
1933 1,322
1934 1,249
1935 1,260
1936 1,447
1937 1,184
1938 1,149
1939 767
1940 774
1941 783
1942 862
1943 915
1944 913
1945 823
1946 1,087
1947 1,368
1948 1,540
1949 1,503
1950 1,461
1951 1,420
1952 1,428
1953 1,290
1954 1,233
1955 1,400
1956 1,284
1957 1,142
1958 1,082
1959 1,048
1960 1,199
1961 1,069
1962 1,287
1963 1,230
1964 1,305
1965 1,236
1966 1,181
1967 1,102
1968 1,178
1969 1,269
1970 1,203
1971 957
1972 1,062
1973 1,215
1974 1,257
1975 1,373
1976 1,392
1977 1,217
1978 1,235
1979 1,228
1980 1,728
1981 1,526
1982 1,508
1983 1,713
1984 1,784
1985 1,286
1986 1,282
1987 1,441
1988 1,571
1989 1,645
1990 1,518
1991 1,611
1992 2,356
1993 2,221
1994 1,874
1995 1,674
1996 1,961
1997 1,491
1998 1,637
1999 2,217
2000 2,474
2001 1,471
2002 1,555
2003 1,320
2004 1,550
2005 1,245
2006 1,250
2007 1,161
2008 1,237
2009 984
2010 975
2011 686
2012 701
2013 547
2014 635
2015 504
2016 381
2017 100

In addition there are 6,872 problems where the year of publication is unknown.


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