GI vs jouster

GI

noun
  • One who is demanding and strict, in the manner of a stereotypical member of the military. 

  • A member of the U.S. military. 

verb
  • To clean aggressively. 

jouster

noun
  • A horse used as a mount when jousting. 

  • A person who jousts. 

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