ambit vs extensity

ambit

noun
  • The extent of actions, thoughts, or the meaning of words, etc. 

  • The area or sphere of control and influence of something. 

extensity

noun
  • The degree to which something is extensive 

  • The state of being extensive or of having extension 

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