out to lunch vs unscrewed

out to lunch

adj
  • Clueless, inattentive, or careless. 

  • Away eating lunch or for a midday break; especially, away from work or a job. 

unscrewed

adj
  • Not having been screwed. 

How often have the words out to lunch and unscrewed occurred in a corpus of books? (source: Google Ngram Viewer )