affability vs formality

affability

noun
  • The state or quality of being affable, friendly, or approachable. 

formality

noun
  • The state of being formal. 

  • Something said or done as a matter of form. 

  • A specific requirement for obtaining a legal status, conducting a transaction, etc. 

  • A customary ritual without new or unique meaning. 

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