drop in the sea vs small change

drop in the sea

noun
  • A very small or insignificant amount; something of little importance. 

small change

noun
  • A minor or insignificant amount of money. 

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

  • A person or thing of little importance or value. 

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