expiry vs off-ramp

expiry

noun
  • End; termination; expiration. 

  • Synonym of expiration date 

  • Death. 

off-ramp

noun
  • An exit strategy. 

  • A segment of roadway that directs vehicular traffic from a freeway onto local roads. 

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