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 678
1850-1859 1,422
1860-1869 926
1870-1879 2,848
1880-1889 4,215
1890-1899 5,725
1900-1909 10,725
1910-1919 11,030
1920-1929 11,028
1930-1939 12,895
1940-1949 11,849
1950-1959 13,844
1960-1969 13,014
1970-1979 13,305
1980-1989 16,624
1990-1999 19,585
2000-2009 15,342
2010-2019 8,189

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 63
1845 34
1846 58
1847 154
1848 97
1849 138
1850 81
1851 67
1852 100
1853 107
1854 91
1855 98
1856 153
1857 197
1858 282
1859 246
1860 204
1861 166
1862 98
1863 41
1864 49
1865 45
1866 51
1867 99
1868 105
1869 68
1870 141
1871 176
1872 194
1873 369
1874 426
1875 304
1876 320
1877 323
1878 339
1879 256
1880 462
1881 489
1882 370
1883 390
1884 363
1885 401
1886 477
1887 358
1888 519
1889 386
1890 482
1891 371
1892 460
1893 505
1894 539
1895 565
1896 637
1897 726
1898 792
1899 648
1900 785
1901 907
1902 963
1903 631
1904 1,074
1905 1,112
1906 1,220
1907 1,239
1908 1,376
1909 1,418
1910 1,241
1911 1,534
1912 1,305
1913 1,001
1914 784
1915 894
1916 982
1917 1,066
1918 1,147
1919 1,076
1920 1,073
1921 1,133
1922 943
1923 816
1924 903
1925 1,178
1926 1,244
1927 1,126
1928 1,274
1929 1,338
1930 1,409
1931 1,214
1932 1,297
1933 1,379
1934 1,323
1935 1,389
1936 1,573
1937 1,268
1938 1,225
1939 818
1940 824
1941 826
1942 881
1943 984
1944 926
1945 1,158
1946 1,368
1947 1,733
1948 1,621
1949 1,528
1950 1,489
1951 1,487
1952 1,522
1953 1,410
1954 1,316
1955 1,558
1956 1,340
1957 1,287
1958 1,230
1959 1,205
1960 1,340
1961 1,122
1962 1,388
1963 1,313
1964 1,397
1965 1,347
1966 1,261
1967 1,197
1968 1,236
1969 1,413
1970 1,243
1971 1,101
1972 1,310
1973 1,302
1974 1,390
1975 1,466
1976 1,468
1977 1,304
1978 1,332
1979 1,389
1980 1,847
1981 1,645
1982 1,642
1983 1,793
1984 1,905
1985 1,391
1986 1,418
1987 1,592
1988 1,671
1989 1,720
1990 1,641
1991 1,673
1992 2,369
1993 2,175
1994 1,927
1995 1,792
1996 2,110
1997 1,715
1998 1,858
1999 2,325
2000 2,761
2001 1,576
2002 1,657
2003 1,398
2004 1,669
2005 1,356
2006 1,282
2007 1,215
2008 1,292
2009 1,136
2010 1,127
2011 832
2012 1,040
2013 840
2014 1,042
2015 848
2016 966
2017 955
2018 525
2019 14

In addition there are 6,874 problems where the year of publication is unknown.


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