The world’s biggest oil companies are struggling to generate enough cash to cover their spending and dividends, despite efforts to slash billions of dollars from their budgets in the face of tumbling oil prices. Analysts say they expect the companies to reveal continuing shortfalls when they report earnings this week, after a third quarter in which oil prices fell to their lowest levels since the financial crisis. Brent crude, the global benchmark, averaged roughly $50 a barrel in the third quarter, compared with more than $60 a barrel in the second and around $100 in 2014. The cash crunch underscores the cloudy future facing Exxon, Chevron, Shell and BP amid a 16-month slump in oil prices. After a decade when high oil prices supported megaprojects and steadily escalating payouts to shareholders, the supermajors have slashed spending by more than $30 billion in recent months, laying off workers and delaying […]