forthcoming vs to be

forthcoming

noun
  • Something that is yet to come. 

  • An act of coming forth. 

adj
  • Available when needed; in place, ready. 

  • Willing to co-operate or provide information; candid, frank, responsive. 

  • Approaching or about to take place. 

to be

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