round the bend vs sane

round the bend

prep
  • Crazy, mad or insane. 

  • Close to or in close proximity to another location. 

sane

adj
  • Being in a healthy condition; not deranged; thinking rationally. 

  • Mentally sound; possessing a rational mind; having the mental faculties in such condition as to be able to anticipate and judge the effect of one's actions in an ordinary manner. 

  • Rational; reasonable; sensible. 

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