Google Books Ngram Viewer

Graph these comma-separated phrases:
case-insensitive
between and from the corpus with smoothing of .  
Search in Google Books:

1800 - 1811 1812 - 1823 1824 - 1835 1836 - 1948 1949 - 2000 very certain English
1800 - 1837 1838 - 1905 1906 - 1918 1919 - 1984 1985 - 2000 absolutely certain English
1800 - 1825 1826 - 1893 1894 - 1907 1908 - 1967 1968 - 2000 very sure English
1800 - 1892 1893 - 1971 1972 - 1982 1983 - 1991 1992 - 2000 absolutely sure English

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