for a fact vs unmetaphorically

for a fact

adv
  • Used other than figuratively or idiomatically: see for, a, fact. 

  • Without doubt. 

unmetaphorically

adv
  • In a way that is not metaphorical. 

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