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 689
1850-1859 1,422
1860-1869 921
1870-1879 2,857
1880-1889 4,253
1890-1899 5,541
1900-1909 7,657
1910-1919 9,033
1920-1929 10,823
1930-1939 12,421
1940-1949 11,618
1950-1959 13,050
1960-1969 12,346
1970-1979 12,369
1980-1989 16,108
1990-1999 19,763
2000-2009 14,896
2010-2019 6,501

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 69
1845 34
1846 58
1847 153
1848 103
1849 138
1850 81
1851 67
1852 100
1853 107
1854 91
1855 97
1856 153
1857 196
1858 282
1859 248
1860 203
1861 166
1862 97
1863 42
1864 48
1865 43
1866 50
1867 97
1868 107
1869 68
1870 143
1871 176
1872 193
1873 377
1874 426
1875 303
1876 329
1877 321
1878 336
1879 253
1880 462
1881 489
1882 376
1883 398
1884 362
1885 398
1886 483
1887 364
1888 532
1889 389
1890 496
1891 394
1892 464
1893 511
1894 555
1895 574
1896 642
1897 740
1898 643
1899 522
1900 653
1901 749
1902 706
1903 630
1904 741
1905 696
1906 825
1907 882
1908 890
1909 885
1910 769
1911 1,071
1912 794
1913 859
1914 725
1915 812
1916 898
1917 975
1918 1,081
1919 1,049
1920 1,062
1921 1,128
1922 938
1923 790
1924 889
1925 1,149
1926 1,232
1927 1,106
1928 1,232
1929 1,297
1930 1,373
1931 1,170
1932 1,265
1933 1,375
1934 1,289
1935 1,316
1936 1,472
1937 1,211
1938 1,172
1939 778
1940 794
1941 799
1942 865
1943 918
1944 920
1945 1,079
1946 1,380
1947 1,750
1948 1,587
1949 1,526
1950 1,479
1951 1,442
1952 1,453
1953 1,310
1954 1,275
1955 1,431
1956 1,297
1957 1,154
1958 1,125
1959 1,084
1960 1,221
1961 1,096
1962 1,334
1963 1,240
1964 1,338
1965 1,273
1966 1,219
1967 1,135
1968 1,184
1969 1,306
1970 1,221
1971 987
1972 1,096
1973 1,239
1974 1,277
1975 1,403
1976 1,418
1977 1,245
1978 1,243
1979 1,240
1980 1,732
1981 1,549
1982 1,555
1983 1,728
1984 1,863
1985 1,354
1986 1,389
1987 1,570
1988 1,662
1989 1,706
1990 1,619
1991 1,657
1992 2,375
1993 2,218
1994 1,965
1995 1,812
1996 2,146
1997 1,728
1998 1,890
1999 2,353
2000 2,577
2001 1,523
2002 1,670
2003 1,407
2004 1,650
2005 1,315
2006 1,303
2007 1,181
2008 1,258
2009 1,012
2010 1,081
2011 783
2012 943
2013 710
2014 861
2015 685
2016 768
2017 653
2018 17

In addition there are 6,965 problems where the year of publication is unknown.


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