Administrator vs first minister

Administrator

noun
  • The queen's representative in some Commonwealth territories, comparable to a Governor General. 

first minister

noun
  • The principal minister of a ruler or state. 

  • A leader of a devolved government such as Scotland, Wales, or Northern Ireland. 

  • The prime minister or a provincial or territorial premier. 

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