confidence vs self-confidence

confidence

noun
  • Self-assurance. 

  • A feeling of certainty; firm trust or belief; faith. 

  • Information held in secret; a piece of information shared but to thence be kept in secret. 

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 confidence and self-confidence occurred in a corpus of books? (source: Google Ngram Viewer )