Google Books Ngram Viewer

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

1938 - 1941 1942 - 1946 1947 - 1966 1967 - 1999 2000 - 2008 porto English
1938 - 1943 1944 - 1947 1948 - 1966 1967 - 1998 1999 - 2008 oporto English

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