Google Books Ngram Viewer

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

1800 - 1813 1814 - 1826 1827 - 1873 1874 - 1975 1976 - 2008 atheism English
1800 - 1838 1839 - 1883 1884 - 1894 1895 - 1991 1992 - 2008 theism English

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