constancy vs transience

constancy

noun
  • The quality of being constant; steadiness or faithfulness in action, affections, purpose, etc. 

  • An unchanging quality or characteristic of a person or thing. 

transience

noun
  • The quality of being transient, temporary, brief or fleeting. 

  • An impermanence that suggests the inevitability of ending or dying. 

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