Investors in the upstream oil and gas industry have been on a roller coaster ride for the past 5 years, with prices reaching dizzying heights and then plummeting. The latest twist on the roller coaster leaves operators with a cost base and tax rates reflecting a price environment that seems to have disappeared. Consequently, company profits are evaporating, and there is huge pressure on future investment plans.Governments of oil-producing countries are hurting, too. With the oil price dropping (and operators' costs increasing), governments' tax margins have been squeezed dramatically. Some governments have reduced their projected levels of oil revenue, impacting the budgets that they esta...