reviewer vs subeditor

reviewer

noun
  • A person who writes reviews for a newspaper or other publication; a critic. 

  • An inspector. 

subeditor

noun
  • A copy editor at a newspaper or magazine. 

  • An assistant editor, usually in a specific department of a newspaper. 

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