Drilling Cost Per Foot Formula & Limitations
Oil well drilling cost per foot is a convenient way of comparing the economic impact of bit performances (Roller cone bit performance - PDC bit performance) on a well that is to be drilled. We are not interested in the absolute, actual, real, or true cost per foot on a real well. Bit prices, rig rates, and other drilling costs may well be different for the planned well, and it is the planned well that we are interested in.
https://www.drillingmanual.com/oil-well-drilling-cost-per-foot-formula-limitations/