essay vs position paper

essay

noun
  • A written composition of moderate length, exploring a particular issue or subject. 

  • A proposed design for a postage stamp or a banknote. 

verb
  • To move forth, as into battle. 

position paper

noun
  • An essay or report which expresses a position, conclusion, or recommendation concerning a contested issue or undecided question and which usually contains arguments or reasons in support of this position. 

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