composure vs unconcern

composure

noun
  • Calmness of mind or temperament 

unconcern

noun
  • Freedom from worry or apprehensiveness; insouciance or nonchalance. 

  • Lack of interest or care; indifference or apathy. 

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