decency vs impurity

decency

noun
  • That which is proper or becoming. 

  • The quality of being decent; propriety. 

impurity

noun
  • A component or additive that renders something else impure. 

  • The condition of being impure; because of contamination, pollution, adulteration or insufficient purification. 

  • A state of immorality or sin; especially the weakness of the flesh: inchastity. 

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