disuse vs go down the toilet

disuse

verb

  • To cease the use of. 

noun

  • The state of not being used; neglect. 

go down the toilet

verb

  • To fail. 

  • Used other than figuratively or idiomatically: see go, down, the, toilet. 

  • To degenerate rapidly. 

How often have the words disuse and go down the toilet occurred in a corpus of books? (source: Google Ngram Viewer )