lasting vs unending

lasting

adj
  • Persisting for an extended period of time. 

noun
  • A durable woollen material formerly used for women's shoes. 

  • The act or process of shaping footwear on a last. 

unending

adj
  • Not ending; having no end; eternal. 

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