Google Books Ngram Viewer

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

1950 - 1963 1964 - 1991 1992 - 1993 1994 - 1998 1999 - 2000 ought not do that English
1950 - 1954 1955 - 1969 1970 - 1972 1973 - 1992 1993 - 2000 ought not to do that English

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