Google Books Ngram Viewer

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

Ngrams not found: April Fool's Day, [April Fool's Day]

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1800 - 1815 1816 - 1985 1986 - 1989 1990 - 1998 1999 - 2000 april fools day English

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