agendum vs order of business

agendum

noun
  • Something to be done; a practical duty, rather than an article of faith. 

order of business

noun
  • A task which needs to be completed. 

  • The sequence in which tasks need to be completed in order of importance or priority; an agenda. 

How often have the words agendum and order of business occurred in a corpus of books? (source: Google Ngram Viewer )