centenarian vs not as young as one was

centenarian

adj
  • Aged 100 years or more; extremely old. 

  • Of or relating to centenarians or a centenary celebration. 

noun
  • One who or that which is at least 100 years old. 

not as young as one was

How often have the words centenarian and not as young as one was occurred in a corpus of books? (source: Google Ngram Viewer )