Untermensch vs troglodyte

Untermensch

noun
  • An inferior person; a subhuman, especially in a Nazi racial hierarchy. 

troglodyte

noun
  • A person who chooses not to keep up-to-date with the latest software and hardware. 

  • A reclusive, reactionary or out-of-date person, especially if brutish. 

  • Anything that lives underground. 

  • The Eurasian wren, Troglodytes troglodytes. 

  • A member of a supposed prehistoric race that lived in caves or holes, a caveman. 

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