in trouble vs on the rack

in trouble

prep
  • Pregnant, unmarried, and not likely to be married before giving birth. 

  • Suffering difficulties. 

  • Liable to be punished for misbehavior; in disgrace. 

adj
  • in a difficult situation 

on the rack

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