The annual benchmark price of iron ore is an overlooked gauge of the global economy. Negotiated each year between the world’s top iron ore miners and steelmakers, it is a strong indicator of demand for almost anything that requires steel: ships, houses, cars, refrigerators.

Last week it emerged that Rio Tinto, the world’s second-biggest iron ore miner, was in talks with Asian steelmakers about cutting its iron ore prices for the contract year starting April 1 by 20 per cent, a target steelmakers view as provisional until a permanent settlement can be reached.