declaring vs indiction

declaring

noun
  • The act of making something known; announcing; proclaiming 

indiction

noun
  • A declaration or official announcement. 

  • A fiscal period of fifteen years, instituted by Constantine in 313 C.E. (but counting from 1st September 312), used throughout the Middle Ages as a way of dating events, documents etc. 

  • The decree made by Roman emperors which fixed the property tax for the next fifteen years. 

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