Oil companies are groping around in the dark. It is hard to be confident that dawn is imminent. In BP’s case, a respectable headline cash-flow figure was flattered by movements in working capital. Excluding those, cash flow from operations dropped sharply from the third quarter to the fourth, leaving BP squarely cash negative after investment for the three months. For 2015 as whole, with earlier quarters helped by strong refining margins downstream and good trading results, BP eked out enough cash flow to cover its nearly-$19 billion in capital expenditure. But the bulk of its dividend had to be paid out of debt. Things are likely to get worse. The average oil price last year was about $54 a barrel. In the fourth quarter, it was $45, and in the first quarter it is already running nearly 30% below that. Refining margins will be lower this quarter, BP said. […]