drover vs grazier

drover

noun
  • A person who drives animals, especially cattle or sheep, over long distances. 

grazier

noun
  • One who grazes cattle and/or sheep on a rural property. 

  • The owner of a large property on which sheep or cattle graze. 

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