11. The recent sustained two-year drop in price is directly paralleled by a similar drop in U.S. and world rotary rig count (per Baker-Hughes reports). In the same time-frame, marginal, highly leveraged producers ceased to be profitable and faced bankruptcy. In future hindsight, this extended period of reduced extraction will look like the tipping point of the oil age. But instead of a classic bell-shaped Hubbert’s curve, oil extraction will be an extended plateau and a sharper cliff.