dead-end vs fluctuate

dead-end

verb
  • To come to a dead-end. 

noun
  • A road with no exit. 

  • A position that offers no hope of progress. 

adj
  • Going nowhere; blocked. 

fluctuate

verb
  • To undulate. 

  • To cause to vary irregularly. 

  • To vary irregularly; to swing. 

  • To be irresolute; to waver. 

How often have the words dead-end and fluctuate occurred in a corpus of books? (source: Google Ngram Viewer )