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 685
1850-1859 1,419
1860-1869 911
1870-1879 2,847
1880-1889 4,221
1890-1899 5,825
1900-1909 8,304
1910-1919 9,092
1920-1929 10,904
1930-1939 12,763
1940-1949 11,752
1950-1959 13,405
1960-1969 12,867
1970-1979 13,001
1980-1989 16,563
1990-1999 19,786
2000-2009 15,188
2010-2019 6,786

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 155
1848 103
1849 138
1850 81
1851 67
1852 100
1853 107
1854 91
1855 97
1856 152
1857 196
1858 281
1859 247
1860 203
1861 166
1862 93
1863 40
1864 48
1865 43
1866 49
1867 97
1868 107
1869 65
1870 141
1871 174
1872 194
1873 374
1874 424
1875 305
1876 326
1877 321
1878 336
1879 252
1880 459
1881 484
1882 372
1883 392
1884 363
1885 398
1886 480
1887 354
1888 531
1889 388
1890 495
1891 398
1892 464
1893 507
1894 556
1895 574
1896 641
1897 741
1898 798
1899 651
1900 824
1901 919
1902 979
1903 633
1904 746
1905 702
1906 829
1907 883
1908 895
1909 894
1910 775
1911 1,077
1912 798
1913 868
1914 735
1915 817
1916 900
1917 981
1918 1,083
1919 1,058
1920 1,071
1921 1,133
1922 942
1923 802
1924 899
1925 1,156
1926 1,235
1927 1,119
1928 1,240
1929 1,307
1930 1,383
1931 1,182
1932 1,273
1933 1,388
1934 1,305
1935 1,359
1936 1,546
1937 1,272
1938 1,229
1939 826
1940 830
1941 830
1942 892
1943 929
1944 930
1945 1,078
1946 1,380
1947 1,749
1948 1,596
1949 1,538
1950 1,494
1951 1,461
1952 1,507
1953 1,339
1954 1,313
1955 1,492
1956 1,326
1957 1,192
1958 1,161
1959 1,120
1960 1,265
1961 1,131
1962 1,384
1963 1,303
1964 1,394
1965 1,337
1966 1,262
1967 1,197
1968 1,248
1969 1,346
1970 1,252
1971 1,091
1972 1,256
1973 1,280
1974 1,318
1975 1,463
1976 1,472
1977 1,282
1978 1,313
1979 1,274
1980 1,751
1981 1,603
1982 1,612
1983 1,797
1984 1,917
1985 1,393
1986 1,442
1987 1,605
1988 1,699
1989 1,744
1990 1,653
1991 1,671
1992 2,373
1993 2,203
1994 1,952
1995 1,812
1996 2,141
1997 1,730
1998 1,887
1999 2,364
2000 2,579
2001 1,545
2002 1,683
2003 1,432
2004 1,688
2005 1,358
2006 1,319
2007 1,209
2008 1,290
2009 1,085
2010 1,107
2011 800
2012 979
2013 745
2014 887
2015 686
2016 779
2017 732
2018 71

In addition there are 6,947 problems where the year of publication is unknown.


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