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 684
1850-1859 1,419
1860-1869 912
1870-1879 2,844
1880-1889 4,199
1890-1899 5,722
1900-1909 9,660
1910-1919 9,512
1920-1929 10,970
1930-1939 12,774
1940-1949 11,822
1950-1959 13,595
1960-1969 13,019
1970-1979 13,349
1980-1989 16,752
1990-1999 19,839
2000-2009 15,160
2010-2019 7,495

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 103
1849 138
1850 81
1851 67
1852 100
1853 107
1854 91
1855 97
1856 152
1857 195
1858 282
1859 247
1860 203
1861 166
1862 93
1863 40
1864 48
1865 43
1866 49
1867 97
1868 107
1869 66
1870 141
1871 175
1872 194
1873 373
1874 426
1875 304
1876 323
1877 320
1878 335
1879 253
1880 460
1881 484
1882 370
1883 392
1884 363
1885 397
1886 479
1887 352
1888 518
1889 384
1890 481
1891 371
1892 456
1893 502
1894 541
1895 564
1896 636
1897 730
1898 794
1899 647
1900 780
1901 907
1902 968
1903 628
1904 1,077
1905 1,114
1906 1,220
1907 1,076
1908 987
1909 903
1910 835
1911 1,124
1912 902
1913 982
1914 753
1915 816
1916 905
1917 1,009
1918 1,109
1919 1,077
1920 1,082
1921 1,141
1922 952
1923 809
1924 903
1925 1,164
1926 1,237
1927 1,120
1928 1,246
1929 1,316
1930 1,388
1931 1,182
1932 1,269
1933 1,386
1934 1,303
1935 1,362
1936 1,559
1937 1,272
1938 1,228
1939 825
1940 830
1941 828
1942 890
1943 989
1944 934
1945 1,077
1946 1,381
1947 1,747
1948 1,607
1949 1,539
1950 1,497
1951 1,489
1952 1,540
1953 1,428
1954 1,315
1955 1,507
1956 1,329
1957 1,193
1958 1,170
1959 1,127
1960 1,276
1961 1,139
1962 1,404
1963 1,328
1964 1,415
1965 1,349
1966 1,265
1967 1,205
1968 1,261
1969 1,377
1970 1,257
1971 1,103
1972 1,276
1973 1,320
1974 1,382
1975 1,486
1976 1,494
1977 1,313
1978 1,357
1979 1,361
1980 1,776
1981 1,620
1982 1,638
1983 1,831
1984 1,928
1985 1,410
1986 1,451
1987 1,623
1988 1,709
1989 1,766
1990 1,682
1991 1,704
1992 2,378
1993 2,212
1994 1,948
1995 1,805
1996 2,134
1997 1,728
1998 1,886
1999 2,362
2000 2,573
2001 1,544
2002 1,681
2003 1,426
2004 1,680
2005 1,360
2006 1,316
2007 1,211
2008 1,286
2009 1,083
2010 1,128
2011 821
2012 1,028
2013 797
2014 977
2015 810
2016 886
2017 886
2018 162

In addition there are 6,967 problems where the year of publication is unknown.


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