duck out vs walk off

duck out

verb
  • To move or act so as to achieve avoidance, escape, or evasion. 

  • To depart quickly or exit abruptly by way of, especially in a manner which does not attract notice and before a meeting, event, etc. has concluded. 

  • To depart quickly or exit abruptly, especially in a manner which does not attract notice and before a meeting, event, etc. has concluded. 

walk off

verb
  • To flee or abandon. 

  • To measure a distance by walking, as by counting paces or extending a measuring tape or rope. 

  • To recover from (a minor injury) or digest (a large meal) by walking around. 

How often have the words duck out and walk off occurred in a corpus of books? (source: Google Ngram Viewer )