Chicano vs wetback

Chicano

noun
  • A Chicano person. 

adj
  • Of or pertaining to Chicano people. 

  • Of a person: American but of Mexican descent, especially if conscious of one's political identity in the U.S. body politic. 

  • Identifying with the mixed-raced heritage of Old World and New World. 

wetback

noun
  • A person of the mestizo race; a mojado. 

  • A Mexican or Central American who illegally enters the United States of America from its southern border. 

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