allegation vs exoneration

allegation

noun
  • The act of alleging. 

  • An assertion, especially an accusation, not necessarily based on facts. 

exoneration

noun
  • An act of disburdening, discharging, or freeing morally from a charge or imputation. 

  • The state of being disburdened or freed from a charge. 

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