Smokey Bear vs state trooper

Smokey Bear

noun
  • A policeman, especially a highway patrol officer. 

  • A firefighter. 

  • A ranger or park service employee that deals with the public. 

  • A campaign hat. 

  • An aircraft used to drop defoliants in the Viet Nam war. 

name
  • A fictional bear dressed as a ranger who acts as a symbol of forest fire prevention, with the slogan "Only you can prevent forest fires." 

state trooper

noun
  • An officer of the state police. 

How often have the words Smokey Bear and state trooper occurred in a corpus of books? (source: Google Ngram Viewer )