phlegmatic vs unconcerned

phlegmatic

adj
  • Not easily excited to action or passion; calm; sluggish. 

  • Generating, causing, or full of phlegm. 

noun
  • One who has a phlegmatic disposition. 

unconcerned

adj
  • Not anxious, apprehensive, or worried. 

  • Having no involvement. 

  • Indifferent and having no interest; aloof. 

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