Google Books Ngram Viewer

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

1940 - 1980 1981 - 2001 2002 - 2003 2004 - 2005 2006 - 2008 ballpark figure English
1940 - 1980 1981 - 2000 2001 - 2002 2003 - 2004 2005 - 2008 ballpark estimate English
1940 - 1977 1978 - 2001 2002 - 2003 2004 - 2005 2006 - 2008 in the same ballpark English
1940 - 1984 1985 - 2004 2005 2006 2007 - 2008 in the ballpark of English

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