excitement vs insouciance

excitement

noun
  • something that excites. 

  • the state of being excited (emotionally aroused). 

insouciance

noun
  • Nonchalance. 

  • Carelessness, heedlessness, indifference, or casual unconcern. 

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