futility vs otiosity

futility

noun
  • The quality of being futile or useless. 

  • Something, especially an act, that is futile. 

  • Unimportance. 

otiosity

noun
  • The state or quality of being otiose. 

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