The poor rich. Mukesh Ambani, India’s wealthiest man, saw his estimated $27bn pile erode by a fifth last year. But that is unlikely to be what is keeping him awake at night. On Friday he announced that earnings at Reliance Industries, the company he chairs and India’s biggest by market capitalisation ($46bn), fell from a year earlier for the second consecutive quarter. That left earnings per share for the year ending in March almost flat.

Part of the problem is the group’s, err, reliance on refining imported oil into fuel for India’s 100m cars and rickshaws (among other complicated sounding products). And Reliance’s key Jamnagar refinery (whose pipes are so long they could link Seattle with Miami) is geared towards refining heavy crude. That was a good idea in the golden years around 2004 when the thick stuff was cheap because there was little capacity to refine it. But now everyone has piled in so demand has pushed up the price. The group’s refining margins were down almost a fifth in the fourth quarter, from a year earlier.

Coupled with that, production has fallen at Reliance’s most important gasfields. Water leaks have not helped. But then there is not much incentive to boost output; New Delhi has capped the group’s sale price at about a quarter of international rates. All told, output and margin conundrums have pushed down return on capital employed to all-time lows. Little wonder Mr Ambani is scrambling for ideas. Reliance’s $14bn gross cash pile must have clouded his judgment – telecoms, a notoriously problematic industry in India, is one of his latest ventures. Which has left Reliance’s price to earnings and book value at their lowest levels in several years. Investors will want to see better brainstorming from Mr Ambani before those shares can be considered cheap.