arduity vs urgency

arduity

noun
  • The state or quality of being arduous; steepness, difficulty. 

urgency

noun
  • Insistence, pressure, urge. 

  • The quality or condition of being urgent. 

  • A sudden and compelling need to urinate that is difficult to defer, associated with conditions such as urinary tract infections and overactive bladder. 

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