Google Books Ngram Viewer

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

Ngrams not found: you 're welcome, [you 're welcome]
The Ngram Viewer is case sensitive. Check your capitalization!

Search in Google Books:

1800 - 1927 1928 - 1979 1980 - 1987 1988 - 1994 1995 - 2000 no worries English
1800 - 1825 1826 - 1893 1894 - 1906 1907 - 1970 1971 - 2000 do not mention it English
1800 - 1810 1811 - 1971 1972 - 1981 1982 - 1990 1991 - 2000 no sweat English

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