unconscionable vs unnecessary

unconscionable

adj
  • Not conscionable; unscrupulous and lacking principles or conscience. 

  • Excessive, imprudent or unreasonable. 

unnecessary

adj
  • Done in addition to requirements; unrequired. 

  • Not needed or necessary. 

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