cheapening vs downtick

cheapening

noun
  • The process by which something is cheapened or made vulgar. 

downtick

noun
  • A small decrease or downward change in something that has been steady or rising. 

  • A stock market transaction or quote at a price below a preceding one. 

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