The original source is Chemical Engineering Magazine published monthly by The McGraw-Hill Companies. The full name of the index is "Chemical Engineering Plant Cost Index". It is for process plants which would include oil refineries. It reflects plant construction costs including materials, labour, buildings, engineering and supervision. It should not be confused with the Marshall & Swift Equipment Cost Index which is for equipment only. The magazine publishes the annual index for the last 5 years and for the months in the current calendar year. I thought it would be interesting to tabulate it back to its beginning, since I happen to have on file some of the earlier pages.