assignee vs power of attorney

assignee

noun
  • one who is appointed to act or speak in place of another; an agent 

  • one to whom rights or property is being transferred 

  • one to whom a thing is assigned 

power of attorney

noun
  • The legal authorisation of one person to act as the agent of another. 

  • A legal document allowing one person to act as the agent of another. 

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