equation vs quota

equation

noun
  • The act or process of equating two or more things, or the state of those things being equal (that is, identical). 

  • An assertion that two expressions are equal, expressed by writing the two expressions separated by an equal sign; from which one is to determine a particular quantity. 

  • A small correction to observed values to remove the effects of systematic errors in an observation. 

quota

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

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

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

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