dispassion vs nonchalance

dispassion

noun
  • Freedom from passion; the absence of passion; an undisturbed state; apathy. 

nonchalance

noun
  • Indifference, unconcern; carelessness; coolness; disregard, detachment. 

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