non-payment vs pay-off

non-payment

noun

  • Antonym: payment 

pay-off

noun

  • A payment. 

  • A reward. 

  • A bribe. 

  • A resolution or justification of an event that has already occurred, especially in fiction. 

How often have the words non-payment and pay-off occurred in a corpus of books? (source: Google Ngram Viewer )