let loose vs shut down

let loose

verb
  • To break wind. 

  • To free; to release from restraint. 

  • To shout, make a loud sound, or perform a sudden, vehement action; to behave in a raucous, frenzied manner. 

shut down

verb
  • To turn off or stop. 

  • To pass (another vehicle), especially quickly. 

  • To close, terminate, or end. 

  • To emotionally withdraw into oneself as a defense mechanism; to block out external stressors. 

How often have the words let loose and shut down occurred in a corpus of books? (source: Google Ngram Viewer )