sit-in vs stop-work

sit-in

noun
  • A peaceful form of protest in which people occupy an area and refuse to leave. 

adj
  • Designed to be sat in. 

stop-work

noun
  • Temporary cessation of labor as a form of protest. 

  • Causing work to cease temporarily for administrative reasons such as safety concerns or legal action. 

How often have the words sit-in and stop-work occurred in a corpus of books? (source: Google Ngram Viewer )