Sam Spade vs private dick

Sam Spade

noun

  • A private detective. 

name

  • The fictional private detective created by Dashiell Hammett who was protagonist of The Maltese Falcon. 

private dick

noun

  • A private investigator; a private detective. 

How often have the words Sam Spade and private dick occurred in a corpus of books? (source: Google Ngram Viewer )