consistency vs invariability

consistency

noun
  • Reliability or uniformity; the quality of being consistent. 

  • Freedom from contradiction; the state of a system of axioms such that none of the propositions deduced from them are mutually contradictory. 

  • Correspondence or compatibility. 

  • The degree of viscosity of something. 

  • Local coherence. 

invariability

noun
  • The quality of being invariable 

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