golden years vs senility

golden years

noun
  • Old age; especially, the leisure years in later life after one has retired from employment. 

  • The period during which someone or something flourishes. 

senility

noun
  • Senescence; the bodily and mental deterioration associated with old age. 

  • The losing of memory and reason due to senescence. 

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