peso vs piastre

peso

noun
  • A former unit of currency in Spain and Spain's colonies, worth 8 reales; the Spanish dollar. 

  • The circulating currency of various Spanish-speaking American countries (Argentina, Chile, Colombia, Cuba, the Dominican Republic, Mexico, and Uruguay) and the Philippines. 

piastre

noun
  • A Spanish or Spanish-American coin and unit of currency, originally worth eight real. 

  • A form of currency currently used as a subunit in the Middle Eastern countries of Egypt, Jordan (partly including Palestine), Lebanon, South Sudan, Sudan, and Syria. 

  • A form of currency formerly used in Cyprus. 

  • A form of currency formerly used in French Indochina. 

  • A form of currency formerly used in the French-speaking parts of Canada. 

  • A form of currency originally used in the Ottoman Empire. 

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