concealment vs disclosure

concealment

noun
  • The practice of keeping secrets. 

  • protection from observation or surveillance. 

  • The condition of being hidden or concealed. 

disclosure

noun
  • The act of revealing something. 

  • That which is disclosed; a previously hidden fact or series of facts that is made known. 

  • The making known of a previously hidden fact or series of facts to another party; the act of disclosing. 

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