Charles Coolidge Parlin (1872 – October 15, 1942[1]) was the American "manager of the division of commercial research of the Curtis Publishing Company" in charge of selling advertising spots in the Saturday Evening Post.

[4] Parlin worked as a member of the United States Food Administration while it was run by Herbert Hoover during World War I before becoming a schoolteacher in De Pere, Wisconsin.

[5][6] He would then move on to be the Principal of the Wausau Senior High School and concurrently as President of the Wisconsin State Teachers' Association.

After six months of interviews with a number of people in the industry, he completed a 460-page survey that "revealed unsuspected facts about where agricultural tools were made, to whom they were sold, when, and where.

The study predicted correctly that the number of grades and makes would be reduced in the future and it "envisaged the dimensions and even the shape of the automobile market."