split the difference vs strike a bargain

split the difference

verb
  • In a financial transaction, to settle on an amount midway between the offer and the asking price. 

  • To choose an option or take a position roughly midway between two opposed alternatives; to compromise. 

strike a bargain

verb
  • To enter into a bargain; to agree upon the conditions of a sale or other transaction. 

How often have the words split the difference and strike a bargain occurred in a corpus of books? (source: Google Ngram Viewer )