GI vs warfighter

GI

noun
  • A member of the U.S. military. 

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

verb
  • To clean aggressively. 

warfighter

noun
  • A soldier (especially of the United States military). 

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