Google Books Ngram Viewer

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

1993 - 1996 1997 - 2003 2004 - 2003 2004 - 2008 2009 - 2008 federal subjects English
1993 - 1994 1995 - 2004 2005 2006 - 2007 2008 constituent entities English

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