capability vs effectivity

capability

noun
  • the power or ability to generate an outcome 

  • A digital token allowing a user or process to interact in a specified way with an object that is subject to access control. 

effectivity

noun
  • The ability or power to be effective. 

  • [Technical documentation] An indication of the product, procedure, or timescale for which an item of information is applicable or effective. 

  • A measure of the effectiveness of something. 

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