The iron ore boom powering the profits of the world’s biggest mining companies is showing no sign of fading thanks to stronger-than-expected Chinese steel demand, according to Forbes.

Despite multiple forecasts over the past 12-months that the iron ore price was overdue for a fall it has done exactly the opposite, rising this week to a new 2020 high of $107 a ton, up 30 percent over the past four months.

Given that the biggest miners produce iron ore at a cash cost of around $13/t that latest price implies a gross profit margin, before accounting and other charges, of close to 700 percent.

As well as stronger-than-expected Chinese demand for steel as it stimulates its economy out of the COVID-19 slowdown, iron ore has been aided by continued production problems in some exporting countries, particularly Brazil.

For three of Australia’s biggest mining companies, BHP, Rio Tinto and Fortescue Metals, the prolonged boom in iron ore has delivered windfall profits.

Rio Tinto is first cab off the reporting rank with its June quarter production report scheduled for release on Friday, followed by the half-year profit and dividend statement on July 29.

Investors are expecting a strong result and generous dividend, lifting Rio Tinto’s share price by 31 percent over the past four months as the twin effects of Chinese demand and a slowdown in Brazilian exports drove the price of its major commodity steadily higher.

BHP follows next week with its fourth quarter operational review on Tuesday and annual results statement on August 18 and while the company’s underlying profit is expected to be similar to last year at $9.4 billion thanks to reduced earnings from oil production, the dividend is expected to rise from $1.08 to $1.31 a share with yield chasers keenly bidding the stock up by 48 percent since mid-March.

Fortescue Metals, a pure-play iron ore miner, will be last to report but almost certainly with the most impressive result because it is not held back by other interests such as BHP’s oil and Rio Tinto’s aluminum.

After its July 30 operations report Fortescue is scheduled to release its profit statement on August 24 with underlying earnings forecast to be up 51 percent at $4.7 billion, good enough to lift the annual dividend by 55 percent to $1.77 a share — delivering its founder an chairman, Andrew Forrest, a $1.77 billion dividend “payday” on his one billion shares in the company.

Investment banks have been uncertain how to value the iron ore miners because their models have consistently predicted a steep fall in the price of the commodity and even now, after being wrong all year, the consensus view of the banks is that iron ore miners will fall.

The latest research notes on the iron ore stocks is a mixed bag. Credit Suisse says sell Rio Tinto while being neutral on BHP and Fortescue. RBC Capital Markets has just upgraded its view of Fortescue from sell to hold.

J.P. Morgan has restricted its latest iron ore research report published yesterday to noting the year-high price for the steel-making material at $107/t while also pointing out that all of major producers are operating on massive profit margins given that their cash cost per ton is running at around $14/t — with BHP and Fortescue the leaders at $13/t.

According to J.P. Morgan’s research note the high ore price is all about Chinese steel output which was up 4% in May compared to the same month last year with the overall steel production rate at an annualized 1.1 billion tons.