Google Books Ngram Viewer

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

1940 - 1992 1993 - 1997 1998 1999 2000 human development index English
1940 - 1966 1967 - 1993 1994 - 1996 1997 - 1999 2000 gross domestic product English
1940 - 1982 1983 - 1997 1998 1999 2000 hdi English

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