imply vs mean to say

imply

verb
  • to hint; to insinuate; to suggest tacitly and avoid a direct statement 

  • to suggest by logical inference 

  • to have as a necessary consequence 

mean to say

verb
  • To imply or intend to convey with one's words; used to correct or clarify one's previous utterance, or to seek such clarification. 

How often have the words imply and mean to say occurred in a corpus of books? (source: Google Ngram Viewer )