Google Books Ngram Viewer

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

1800 - 1819 1820 - 1835 1836 - 1848 1849 - 1978 1979 - 2000 couch English
1800 - 1841 1842 - 1861 1862 - 1874 1875 - 1982 1983 - 2000 sofa English

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