decadence vs immorality

decadence

noun
  • A state of moral or artistic decline or deterioration; decay 

  • The quality of being luxuriously self-indulgent. 

immorality

noun
  • The state or quality of being immoral; vice. 

  • An immoral act or practice. 

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