millionaire vs very rich person

millionaire

noun
  • A person whose net worth is at or greater than one million units of the local currency, but less than two million. 

  • A person whose net worth is at or greater than one million units of the local currency; a multimillionaire. 

very rich person

How often have the words millionaire and very rich person occurred in a corpus of books? (source: Google Ngram Viewer )