Google Books Ngram Viewer

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

1960 - 1974 1975 - 1984 1985 - 1986 1987 - 1994 1995 - 2008 methaqualone English

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