Google Books Ngram Viewer

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

1800 - 1825 1826 - 1965 1966 - 1971 1972 - 1983 1984 - 2000 in congo English
1800 - 1908 1909 - 1963 1964 - 1966 1967 - 1985 1986 - 2000 in the congo English

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