shortness vs unavailability

shortness

noun
  • The property of being short or terse. 

  • The property of being short, of being small of stature or brief. 

  • The result or product of being short. 

unavailability

noun
  • The state of being unavailable 

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