Crude oil supply curves

Crude oil supply curves Adelman, Morris Albert Short-run cost curves shift over time as depletion counters increasing knowledge. Under competition, a rightward (leftward) shift indicates lower (higher) cost and greater (lesser) productivity. A simple coefficient captures the slope, and its changes. USA crude oil productivity rose for many years, declined after 1972. In natural gas it can only be discerned since 1984, but has if anything increased. OPEC productivity rose greatly before 1970, refl