datum vs punch line

datum

noun
  • A premise from which conclusions are drawn. 

  • A floating reference point, or SLDMB, used to evaluate surface currents in a body of water. Often employed by coastal search and rescue. 

  • A fixed reference point or set of reference points which precisely define a system of measurement or a coordinate system. 

  • A fact known from direct observation. 

verb
  • To provide missing data points by using a mathematical model to extrapolate values that are outside the range of a measuring device. 

punch line

noun
  • A final, concluding statement that an explanation has been leading up to; a conclusion. 

  • The butt of a joke; laughing stock. 

  • The final part of a joke; the word, sentence, or exchange of sentences that is intended to be funny and provokes laughter from the listeners. 

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