aplomb vs self-confidence

aplomb

noun
  • Self-confidence; poise; composure. 

  • The apparent elegance and precision exhibited by a confident, accomplished dancer. 

  • The perpendicular; perpendicularity. 

self-confidence

noun
  • The state of being self-confident 

  • A measure of one's belief in one's own abilities 

How often have the words aplomb and self-confidence occurred in a corpus of books? (source: Google Ngram Viewer )