angst vs nonchalance

angst

noun
  • A feeling of acute but vague anxiety or apprehension often accompanied by depression, especially philosophical anxiety. 

  • Emotional turmoil; painful sadness. 

verb
  • To suffer angst; to fret. 

nonchalance

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

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