hang up one's boots vs pension

hang up one's boots

verb
  • retire, call it a day 

pension

verb
  • To force (someone) to retire on a pension. 

  • To grant a pension to. 

noun
  • An annuity paid regularly as benefit due to a retired employee, serviceman etc. in consideration of past services, originally and chiefly by a government but also by various private pension schemes. 

  • A sum paid to a clergyman in place of tithes. 

  • A boarding house or small hotel, especially in continental Europe, which typically offers lodging and certain meals and services. 

  • A regular allowance paid to support a royal favourite, or as patronage of an artist or scholar. 

How often have the words hang up one's boots and pension occurred in a corpus of books? (source: Google Ngram Viewer )