narrator vs spokesperson

narrator

noun
  • The person or the "voice" whose viewpoint is used in telling a story. 

  • One who narrates or tells stories. 

  • The person providing the voice-over in a documentary. 

spokesperson

noun
  • A person who acts as the voice of another person or a group of people. 

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