Google Books Ngram Viewer

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

1800 - 1829 1830 - 1936 1937 - 1950 1951 - 1986 1987 - 2000 had not known English
1800 - 1840 1841 - 1938 1939 - 1952 1953 - 1987 1988 - 2000 did not know English

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