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 - 1951 1952 - 1970 1971 - 1987 1988 - 2000 rights English
1800 - 1815 1816 - 1829 1830 - 1842 1843 - 1957 1958 - 2000 duty English

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