employment vs one’s specialty

employment

noun
  • 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 

  • A use, purpose 

  • The state of being employed 

one’s specialty

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