Google Books Ngram Viewer

Graph these comma-separated phrases:
case-insensitive
between and from the corpus with smoothing of .  
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1800 - 1984 1985 - 1994 1995 1996 - 1997 1998 - 2000 insecticidal soap English
1800 - 1945 1946 1947 - 1972 1973 - 1994 1995 potassium salts of fatty acids English

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