Years


DecadeNumber of problems
1280-1289 1
1300-1309 5
1350-1359 6
1490-1499 8
1510-1519 1
1600-1609 6
1730-1739 6
1750-1759 3
1760-1769 8
1780-1789 1
1800-1809 5
1810-1819 3
1820-1829 7
1830-1839 35
1840-1849 681
1850-1859 1,416
1860-1869 911
1870-1879 2,839
1880-1889 4,189
1890-1899 5,708
1900-1909 10,519
1910-1919 9,803
1920-1929 11,074
1930-1939 12,804
1940-1949 11,835
1950-1959 13,842
1960-1969 12,960
1970-1979 13,319
1980-1989 16,683
1990-1999 19,761
2000-2009 15,372
2010-2019 7,789

YearNumber of problems
1283 1
1300 5
1350 6
1497 8
1512 1
1600 5
1604 1
1737 6
1750 3
1763 3
1766 1
1769 4
1787 1
1800 1
1802 1
1806 3
1813 1
1814 1
1817 1
1821 1
1822 1
1823 1
1826 3
1829 1
1830 1
1832 4
1835 1
1836 4
1837 23
1838 2
1840 1
1841 20
1842 87
1843 26
1844 62
1845 34
1846 58
1847 155
1848 100
1849 138
1850 81
1851 67
1852 100
1853 107
1854 91
1855 97
1856 152
1857 194
1858 282
1859 245
1860 203
1861 166
1862 93
1863 40
1864 48
1865 43
1866 48
1867 97
1868 107
1869 66
1870 141
1871 176
1872 194
1873 371
1874 426
1875 303
1876 320
1877 320
1878 335
1879 253
1880 460
1881 482
1882 369
1883 391
1884 363
1885 396
1886 472
1887 354
1888 518
1889 384
1890 479
1891 370
1892 457
1893 501
1894 540
1895 563
1896 635
1897 725
1898 792
1899 646
1900 779
1901 906
1902 965
1903 630
1904 1,078
1905 1,116
1906 1,219
1907 1,240
1908 1,385
1909 1,201
1910 853
1911 1,128
1912 904
1913 981
1914 779
1915 889
1916 985
1917 1,064
1918 1,147
1919 1,073
1920 1,074
1921 1,134
1922 951
1923 817
1924 907
1925 1,176
1926 1,243
1927 1,135
1928 1,279
1929 1,358
1930 1,423
1931 1,222
1932 1,291
1933 1,357
1934 1,299
1935 1,359
1936 1,542
1937 1,257
1938 1,230
1939 824
1940 827
1941 831
1942 889
1943 986
1944 931
1945 1,081
1946 1,376
1947 1,744
1948 1,629
1949 1,541
1950 1,503
1951 1,497
1952 1,541
1953 1,428
1954 1,322
1955 1,561
1956 1,344
1957 1,290
1958 1,238
1959 1,118
1960 1,270
1961 1,131
1962 1,398
1963 1,324
1964 1,408
1965 1,346
1966 1,262
1967 1,200
1968 1,253
1969 1,368
1970 1,252
1971 1,102
1972 1,275
1973 1,312
1974 1,398
1975 1,481
1976 1,482
1977 1,310
1978 1,350
1979 1,357
1980 1,826
1981 1,620
1982 1,615
1983 1,814
1984 1,916
1985 1,401
1986 1,437
1987 1,610
1988 1,693
1989 1,751
1990 1,673
1991 1,700
1992 2,371
1993 2,203
1994 1,944
1995 1,800
1996 2,121
1997 1,721
1998 1,874
1999 2,354
2000 2,737
2001 1,537
2002 1,674
2003 1,415
2004 1,676
2005 1,360
2006 1,314
2007 1,224
2008 1,298
2009 1,137
2010 1,127
2011 821
2012 1,028
2013 807
2014 981
2015 815
2016 943
2017 922
2018 345

In addition there are 6,948 problems where the year of publication is unknown.


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