disuse vs nonchalance

disuse

noun
  • The state of not being used; neglect. 

verb
  • To cease the use of. 

nonchalance

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

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