income vs royalty

income

noun
  • Money coming in to a fund, account, or policy. 

  • Money one earns by working or by capitalising on the work of others. 

  • A disease or ailment without known or apparent cause, as distinguished from one induced by accident or contagion; an oncome. 

  • That which is taken into the body as food; the ingesta; sometimes restricted to the nutritive, or digestible, portion of the food. 

royalty

noun
  • Payment made to a writer, composer, inventor etc for the sale or use of intellectual property, invention etc. 

  • The payment received by an owner of real property for exploitation of mineral rights in the property. 

  • Someone in a privileged position. 

  • A king and a queen as a starting hand in Texas hold 'em. 

  • The bounds of a royal burgh. 

  • A royal right or prerogative, such as the exploitation of a natural resource; the granting of such a right; payment received for such a right. 

  • People of royal rank, plus their families, treated as a group. 

  • The rank, status, power or authority of a monarch. 

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