prorate vs quota

prorate

verb
  • To divide proportionately, especially by day; to divide pro rata. 

quota

noun
  • A restriction on the import of something to a specific quantity. 

  • A proportional part or share; the share or proportion assigned to each in a division. 

  • A prescribed number or percentage that may serve as, for example, a maximum, a minimum, or a goal. 

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