need vs urgency

need

noun
  • A requirement for something; something needed. 

  • Lack of means of subsistence; poverty; indigence; destitution. 

verb
  • To be obliged or required (to do something). 

  • To be required; to be necessary. 

  • To want strongly; to feel that one must have something. 

  • To have an absolute requirement for. 

urgency

noun
  • The quality or condition of being urgent. 

  • Insistence, pressure, urge. 

  • 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 need and urgency occurred in a corpus of books? (source: Google Ngram Viewer )