accountable vs unreliable

accountable

adj
  • Obliged, when called upon, to answer (for one’s deeds); answerable. 

  • Liable to be called on to render an account. 

  • Capable of being accounted for; explicable; explainable. 

  • Obliged to keep accurate records (of property or funds). 

unreliable

adj
  • Not reliable. 

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