buy into vs fund

buy into

verb
  • To buy stocks or shares of (a business). 

  • To believe; to accept a craze or fad as valid. 

fund

verb
  • To form a debt into a stock charged with interest. 

  • To place (money) in a fund. 

  • To pay or provide money for. 

noun
  • A sum or source of money. 

  • An organization managing such money. 

  • A large supply of something to be drawn upon. 

  • A money-management operation, such as a mutual fund. 

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