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 3
1820-1829 7
1830-1839 33
1840-1849 680
1850-1859 1,417
1860-1869 902
1870-1879 2,813
1880-1889 4,180
1890-1899 5,444
1900-1909 7,462
1910-1919 8,805
1920-1929 10,178
1930-1939 12,032
1940-1949 10,561
1950-1959 12,779
1960-1969 12,054
1970-1979 12,135
1980-1989 15,500
1990-1999 18,535
2000-2009 14,246
2010-2019 4,460

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
1811 1
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 245
1860 198
1861 167
1862 95
1863 41
1864 46
1865 41
1866 48
1867 96
1868 105
1869 65
1870 140
1871 172
1872 191
1873 375
1874 424
1875 293
1876 323
1877 318
1878 327
1879 250
1880 455
1881 479
1882 367
1883 394
1884 359
1885 395
1886 474
1887 355
1888 521
1889 381
1890 471
1891 382
1892 459
1893 501
1894 543
1895 564
1896 631
1897 738
1898 636
1899 519
1900 646
1901 745
1902 698
1903 621
1904 731
1905 678
1906 804
1907 871
1908 850
1909 818
1910 737
1911 1,057
1912 780
1913 841
1914 711
1915 780
1916 883
1917 934
1918 1,055
1919 1,027
1920 1,021
1921 1,090
1922 928
1923 761
1924 830
1925 1,061
1926 1,100
1927 999
1928 1,151
1929 1,237
1930 1,316
1931 1,134
1932 1,220
1933 1,322
1934 1,246
1935 1,254
1936 1,446
1937 1,183
1938 1,146
1939 765
1940 774
1941 783
1942 863
1943 914
1944 913
1945 824
1946 1,082
1947 1,366
1948 1,539
1949 1,503
1950 1,460
1951 1,420
1952 1,428
1953 1,288
1954 1,232
1955 1,400
1956 1,283
1957 1,140
1958 1,080
1959 1,048
1960 1,199
1961 1,067
1962 1,287
1963 1,231
1964 1,303
1965 1,235
1966 1,181
1967 1,102
1968 1,179
1969 1,270
1970 1,201
1971 957
1972 1,062
1973 1,215
1974 1,257
1975 1,373
1976 1,393
1977 1,217
1978 1,234
1979 1,226
1980 1,731
1981 1,527
1982 1,508
1983 1,717
1984 1,790
1985 1,286
1986 1,282
1987 1,441
1988 1,572
1989 1,646
1990 1,518
1991 1,611
1992 2,355
1993 2,221
1994 1,875
1995 1,673
1996 1,953
1997 1,491
1998 1,628
1999 2,210
2000 2,474
2001 1,471
2002 1,554
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 699
2013 546
2014 632
2015 502
2016 375
2017 45

In addition there are 6,868 problems where the year of publication is unknown.


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