amass vs clock up

amass

verb
  • to gather a great quantity of; to accumulate. 

  • To accumulate; to assemble. 

  • To collect into a mass or heap. 

clock up

verb
  • To accumulate (an amount of time or experience). 

  • To cover (a distance) over time. 

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