Google Books Ngram Viewer

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

1800 - 1817 1818 1819 - 1866 1867 - 1974 1975 - 2000 from congo English
1800 - 1894 1895 - 1960 1961 - 1965 1966 - 1981 1982 - 2000 from the congo English

Run your own experiment! Raw data is available for download here.
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