continuance vs immutability

continuance

noun
  • The action of continuing. 

  • An order issued by a court granting a postponement of a legal proceeding for a set period. 

immutability

noun
  • The state of being unchangeable in the memory after creation. 

  • The state or quality of being immutable; immutableness. 

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