pocket money vs small potatoes

pocket money

noun
  • A small sum of cash, carried on the person, for small, daily expenses. 

  • A small sum of money given to a child, by a parent or guardian. 

small potatoes

noun
  • One or more persons or things of relatively little consequence, importance, or value. 

How often have the words pocket money and small potatoes occurred in a corpus of books? (source: Google Ngram Viewer )