Google Books Ngram Viewer

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

1980 - 1994 1995 - 2001 2002 2003 - 2005 2006 - 2008 adhd English
1980 - 1983 1984 - 1996 1997 - 1998 1999 - 2005 2006 - 2008 add English

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