Google Books Ngram Viewer

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

1800 - 1866 1867 - 1913 1914 - 1918 1919 - 1949 1950 - 2000 teaspoonfuls English
1800 - 1846 1847 - 1859 1860 - 1869 1870 - 1971 1972 - 2000 teaspoonsful English

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