disturb vs rock the boat

disturb

verb
  • to divert, redirect, or alter by disturbing. 

  • to confuse a quiet, constant state or a calm, continuous flow, in particular: thoughts, actions or liquids. 

  • to have a negative emotional impact; to cause emotional distress or confusion. 

rock the boat

verb
  • To disturb the status quo or go against rules or conventions, as in an effort to get attention. 

  • I'd just jump in and fix it, but that's not my job, and I don't want to rock the boat. 

How often have the words disturb and rock the boat occurred in a corpus of books? (source: Google Ngram Viewer )