Google Books Ngram Viewer

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

1955 - 1966 1967 - 1980 1981 - 1984 1985 - 2003 2004 - 2014 critical path English
1955 - 1980 1981 - 2003 2004 - 2005 2006 - 2007 2008 - 2014 project management English

Run your own experiment! Raw data is available for download here.
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