contribute vs shell out

contribute

verb
  • To give something that is or becomes part of a larger whole. 

shell out

verb
  • To pay money, to disburse; especially, to pay a great deal of money. 

  • To use a program's "shell escape" function to execute an unrelated command or to invoke a subsidiary, interactive shell. 

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