apathy vs potency

apathy

noun
  • Lack of emotion or motivation; lack of interest or enthusiasm towards something; disinterest (in something). 

potency

noun
  • Concentration; strength 

  • Sexual virility: the ability to become erect or achieve orgasm. 

  • Potentiality, ability, capacity. 

  • Power, authority. 

  • The ability or capacity to perform something 

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