deterioration vs downfall

deterioration

noun
  • The process of making or growing worse, or the state of having grown worse. 

downfall

noun
  • A precipitous decline in fortune; death or rapid deterioration, as in status or wealth. 

  • The cause of such a fall; a critical blow or error. 

  • An act of falling down. 

verb
  • To fall down; deteriorate; decline. 

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