potty vs three stops short of Dagenham

potty

adj
  • Insane. 

  • Easy to pot the ball on. 

verb
  • Synonym of go potty 

noun
  • A chamber pot, particularly (children) the pot used when toilet-training children. 

  • Any other device or place for urination or defecation: a toilet; a lavatory; a latrine; an outhouse. 

three stops short of Dagenham

adj
  • Crazy; mad. 

How often have the words potty and three stops short of Dagenham occurred in a corpus of books? (source: Google Ngram Viewer )