Google Books Ngram Viewer

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

1800 - 1967 1968 - 1978 1979 1980 - 1998 1999 - 2000 ilr school English

Run your own experiment! Raw data is available for download here.
© 2013 Google - Privacy & Terms - About Google - About Google Books - About Ngram Viewer