out on one's feet vs unconscious

out on one's feet

adj
  • Stupefied; dazed; nonfunctional. 

  • Standing erect but not consciously aware of one's surroundings, or only minimally aware, and having little or no ability to control one's bodily actions, as a result of physical injury or exhaustion. 

unconscious

adj
  • Not awake; having no awareness. 

  • engaged in skilled performance without conscious control. 

  • Without directed thought or awareness. 

noun
  • That part of mind that is not consciously perceived. 

How often have the words out on one's feet and unconscious occurred in a corpus of books? (source: Google Ngram Viewer )