dollar vs small change

dollar

noun
  • A quarter of a pound or one crown, historically minted as a coin of approximately the same size and composition as a then-contemporary dollar coin of the United States, and worth slightly more. 

  • Official designation for currency in some parts of the world, including Canada, the United States, Australia, New Zealand, Hong Kong, and elsewhere. Its symbol is $. 

  • Money generally. 

  • Imported from the United States, and paid for in U.S. dollars. (Note: distinguish "dollar wheat", North American farmers' slogan, meaning a market price of one dollar per bushel.) 

  • A unit of reactivity equal to the interval between delayed criticality and prompt criticality. 

small change

noun
  • Coins of little value kept in one's pocket or bag. 

  • A minor or insignificant amount of money. 

  • A person or thing of little importance or value. 

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