employment vs usuage

employment

noun
  • A use, purpose 

  • The act of employing 

  • An activity to which one devotes time 

  • The number or percentage of people at work 

  • The work or occupation for which one is used, and often paid 

  • The state of being employed 

usuage

noun
  • consumption or utilisation 

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