pamphlet vs prospectus

pamphlet

noun
  • Such a work containing political material or discussing matters of controversy. 

  • A small, brief printed work, consisting either of a folded sheet of paper, or several sheets bound together into a booklet with only a paper cover, formerly containing literary compositions, newsletters, and newspapers, but now chiefly informational matter. 

verb
  • To distribute pamphlets (to someone or some place). 

  • To distribute pamphlets. 

prospectus

noun
  • A document which describes a proposed endeavor (venture, undertaking), such as a literary work (which one proposes to write). 

  • A booklet or other document giving details of a share offer for the benefit of investors. 

  • A document, distributed to prospective members, investors, buyers, or participants, which describes an institution (such as a university), a publication, or a business and what it has to offer. 

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