Oil shale economics deals with the economic feasibility of oil shale extraction and processing. Although usually oil shale economics is understood as shale oil extraction economics, the wider approach evaluates usage of oil shale as whole, including for the oil-shale-fired power generation and production of by-products during retorting or shale oil upgrading processes. The economic feasibility of oil shale is highly dependent on the price of conventional oil, and the assumption that the price will remain at a certain level for some time to come. As a developing fuel source the production and processing costs for oil shale are high due to the small nature of the projects and the specialist technology involved. A full-scale project to develop oil shale would require heavy investment and could potentially leave businesses vulnerable should the oil price drop and the cost of producing the oil would exceed the price they could obtain for the oil. Due to the volatile prices and high capital costs few deposits can be exploited economically without subsidies. However, some countries, such as Estonia, Brazil, and China, operate oil-shale industries, while some others, including Australia, United States, Canada, Jordan, Israel, and Egypt, are contemplating establishing or re-establishing this industry. The production cost of a barrel of shale oil ranges from as high as US$95 per barrel to as low US$25 per barrel, although there is no recent confirmation of the latter figure. The industry is proceeding cautiously, due to the losses incurred during the last major investment into oil shale in the early 1980s, when a subsequent collapse in the oil price left the projects uneconomic. Break-even price of crude oil The various attempts to develop oil shale deposits have succeeded only when the cost of shale-oil production in a given region comes in below the price of crude oil or its other substitutes (break-even price). The United States Department of Energy estimates that the ex-situ processing would be economic at sustained average world oil prices above US$$54 per barrel and in-situ processing would be economic at prices above $35 per barrel. These estimates assume a return rate of 15%. The International Energy Agency estimates, based on the various pilot projects, that investment and operating costs would be similar to those of Canadian oil sands, that means would be economic at prices above $60 per barrel at current costs. This figure does not account carbon pricing, which will add