behoove vs require

behoove

verb
  • To befit, be appropriate or necessary to somebody. Alternative form of behove. 

  • To be fitting. 

require

verb
  • Naturally to demand (something) as indispensable; to need, to call for as necessary. 

  • To demand, to insist upon (having); to call for authoritatively. 

  • To demand of (someone) to do something. 

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