LONDON – Rio Tinto Group has to work twice as hard to turn the profit it did a decade ago.

Back in 2004, the world’s second-biggest mining company produced about 60-million metric tons of iron ore and reported underlying earnings of $1.3-billion in the second half of the year. Now it extracts about 130-million tons in six months for roughly the same profit.

The numbers show how Rio, like the rest of the mining industry, has been a victim of it’s own success. The company poured $90-billion into expanding production in the last decade, mostly in iron ore, its primary earnings driver, as China’s unprecedented economic boom led to soaring commodity prices and delivered record profits in the years leading up to 2011.

However, when China’s economy began to sputter, mining companies kept investing, churning out more raw materials despite weakening demand, causing prices to collapse. At the time, companies argued that if they didn’t expanded production, others would and erode their market share.

“The volume over price strategy, adopted by not just Rio Tinto but by all of the majors, has been a net failure,” Richard Knights, a mining analyst at Liberum Capital Ltd. in London, said by phone. “With the benefit of hindsight, I think we can say that more disciplined supply would’ve been better for the whole industry as it would have extended the period of super-normal profits.”

Rio, which also produces aluminum and copper, reported underlying earnings of $1.56-billion for the first half, the lowest since 2004. It’s a long way from the record $8.2-billion profit from the second half of 2010, when iron ore was approaching $200 a ton. The steel-making ingredient is now about $60 a ton.

With commodity prices staying depressed, mining companies have been forced to get leaner by reducing costs and cutting dividends. Rio said Wednesday that it would cut the dividend in half, reflecting a new policy to pay out a%age of earnings.

Rio plans to spend less than $4-billion this year, down from almost $18-billion in 2012, said Chief Executive Officer Jean Sebastien Jacques, who last month became CEO after years of running the copper business. He emphasized a strategy of investing in existing projects and expanding profitable operations, rather than focusing on mergers and acquisitions.

“Have we learned from the past? I think we have. I truly believe we have,” Jacques told reporters in London. “We are very clear that we have little capital available to be spent because that’s one of the key criticisms we’ve had in the past. At the peak of the cycle, we were spending too much money.”

The outlook presented on Wednesday provided little scope for optimism. Rio struck a cautious tone in describing China, responsible for almost half of its sales, as being on a “long transition path of slower and less commodity-intensive growth,” according to the company’s statement.

Still, there are signs that business is stabilizing. Rio shares rallied 22% this year, rebounding from a 34% rout in 2015. The company is adjusting to weaker demand growth in a post-China boom era, according to Peter O’Connor, a Sydney-based analyst with Shaw and Partners Ltd.

“We are back to a normal world of growth,” O’Connor said by phone. “It’s not a bad world, it’s what we had for four decades or so. It’s just not offering growth rates of 5 to 10%.”