Google Books Ngram Viewer

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

1800 - 1929 1930 - 1974 1975 - 1977 1978 - 1992 1993 - 2000 economy problem English
1800 - 1854 1855 - 1886 1887 - 1891 1892 - 1964 1965 - 2000 economical problem English

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