Iron-ore exports from Australia’s Port Hedland climbed to an all-time high in June as miners in the largest shipper increased low-cost output, hurting the outlook for prices as steel production slows in China.

Total shipments jumped b 14% to 38.4-million tons last month from a year earlier, according to the Pilbara Ports Authority. That exceeded the previous record of 38-million tons in May, according to authority data compiled by Bloomberg. Exports to China amounted to 32.6-million tons in June, also a record.

The surge in cargo from Australia and from Brazil, which reported that June’s shipments were the highest this year, may hurt prices, which rallied in the second quarter. Supply growth in Australia will accelerate during this half, according to UBS, which said last week that prices were expected to drop as Rio Tinto Group expanded facilities and a new mine backed by billionaire Gina Rinehart started operations.

“This is just further evidence the majors are continuing to push the tons,” says Paul Gait, an analyst at Sanford C Bernstein & Co, in London. “Clearly, that’s bad for prices – there’s no way that could be interpreted positively.”

Exports of iron-ore from Port Hedland totalled 220.8-million tons in the first six months, 13% more than a year earlier, according to Bloomberg calculations. Shipments to China from the Western Australian port expanded by 16.5% to 186-million tons over the same period.

Ore with 62% iron content delivered to Qingdao, which bottomed at $47.08/t on April 2, dropped 6% to $55.63/t last week, the biggest decline in a year, according to data from Metal Bulletin. The benchmark rose 16% in the three months to June after exports from Australia and Brazil missed expectations.

Shipments from Australia may expand by 10% next year, more than twice the rate forecast for 2015, the Australian government said in a quarterly forecast released last week, citing additional supplies from Rinehart’s Roy Hill, as well as expansions by producers including Rio.

Overseas sales from Brazil, the second- biggest exporter, surged to 32-million tons in June, according to the Trade Ministry, compared with 29.55-million tons a year earlier.

Port Hedland is the world’s largest bulk- export terminal. The facility handles cargoes of iron-ore from BHP Billiton and Fortescue Metals Group, Australia’s largest producers after Rio Tinto.

Prices are expected to drop to average $50/t in the second half, according to UBS, which raised its full-year price forecast to $56/t from $50/t, citing the disruptions to supply seen in the first six months. Citigroup sees prices dropping to less than $40/t in the fourth quarter as supplies increase.