compliment vs congratulate

compliment

verb
  • To pay a compliment (to someone); to express a favourable opinion (of someone). 

noun
  • An expression of praise, congratulation, or respect. 

  • Complimentary language; courtesy, flattery. 

congratulate

verb
  • To express one’s sympathetic pleasure or joy to the person(s) it is felt for. 

  • To consider oneself fortunate in some matter. 

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