Rio Tinto has downgraded its iron ore export target for the third consecutive year in a horror quarterly update that announced production downgrades in multiple business units and included yet another delay to Mongolia’s Oyu Tolgoi copper project.

Iron ore is Australia’s most lucrative export and Rio is the biggest exporter of the commodity, but a lack of investment in its flagship business over the past decade has left the company struggling to produce both the volumes and quality of product it is traditionally known for.