Google Books Ngram Viewer

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

1800 - 1891 1892 - 1910 1911 - 1919 1920 - 1995 1996 - 2008 headquarters are English
1800 - 1915 1916 - 1972 1973 - 1978 1979 - 2000 2001 - 2008 headquarters is English

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