comedown vs damp squib

comedown

noun
  • A sudden drop to a lower status, condition or level; a disappointment or letdown. 

  • A calm, mellow period experienced after the initial high from taking drugs. 

damp squib

noun
  • Anything that doesn’t work properly, or fails to come up to expectations; a dud. 

  • A firework that has been wet and therefore fails to go off correctly. 

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