Google Books Ngram Viewer

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

1600 - 1750 1751 - 1776 1777 1778 - 1806 1807 - 1839 freelance English
1600 - 1718 1719 1720 - 1777 1778 - 1801 1802 - 1845 free lance English

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