plummet vs take a dive

plummet

verb
  • To drop swiftly, in a direct manner; to fall quickly. 

noun
  • A violent or dramatic fall. 

  • A decline; a fall; a drop. 

take a dive

verb
  • To decline rapidly. 

  • To lose or fail intentionally. 

  • To feign a knockout in order to lose intentionally. 

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