mischance vs natural disaster

mischance

noun
  • A mishap, an unlucky circumstance. 

  • Bad luck, misfortune. 

verb
  • To undergo (a misfortune); to suffer (something unfortunate). 

natural disaster

noun
  • The emergency situation that is the consequence of such an event. 

  • Any natural phenomenon that causes great damage and loss of life. 

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