rebut vs refute

rebut

verb
  • To deny the truth of something, especially by presenting arguments that disprove it. 

  • To drive back or beat back; to repulse. 

refute

verb
  • To deny the truth or correctness of (something). 

  • To prove (something) to be false or incorrect. 

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