banknote vs paper money

banknote

noun
  • A piece of paper currency. 

  • A promissory note issued by a bank, payable at a given time to a specific beneficiary. 

paper money

noun
  • Cash in the form of banknotes. 

  • A type of joss paper resembling banknotes burnt to venerate the deceased, ancestor spirits, deities, etc. 

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