conclusive vs decisive

conclusive

adj
  • Providing an end to something; decisive. 

  • Pertaining to a conclusion. 

decisive

adj
  • Having the power or quality of deciding a question or controversy; putting an end to contest or controversy; final; conclusive. 

  • Marked by promptness and decision. 

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