agitation vs upheaval

agitation

noun
  • The act of agitating, or the state of being agitated; the state of being disrupted with violence, or with irregular action; commotion. 

  • A disturbance of personal tranquillity; disturbance of someone's peace of mind. 

  • Excitement of public feeling by discussion, appeals, etc. 

upheaval

noun
  • A sudden violent upset, disruption or convulsion. 

  • Disruptive change, from one state to another. 

  • The process of being heaved upward, especially the raising of part of the earth's crust. 

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