archaic vs past its prime

archaic

adj
  • Of or characterized by antiquity; old-fashioned, quaint, antiquated. 

  • Belonging to the archaic period 

  • No longer in ordinary use, though still used occasionally to give a sense of antiquity and are still likely to be understood by well-educated speakers and are found in historical texts. 

noun
  • A general term for the prehistoric period intermediate between the earliest period (‘Paleo-Indian’, ‘Paleo-American’, ‘American‐paleolithic’, &c.) of human presence in the Western Hemisphere, and the most recent prehistoric period (‘Woodland’, etc.). 

  • (A member of) an archaic variety of Homo sapiens. 

past its prime

How often have the words archaic and past its prime occurred in a corpus of books? (source: Google Ngram Viewer )