Chile January copper output tumbled 7.6%

Copper output in Chile, the world's largest copper producer, tumbled 7.6% in the last 12 months to 396,341 metric tons, the National Statistics Institute (INE), a government statistics agency, announced this morning.

The agency attributed the drop to lower ore grades, or the amount of copper found in mined material, falling ore stocks and “mining difficulties."

This year, the INE adjusted the way it calculates the industrial production index to take into account the mining, manufacturing and electricity sectors, making it a broader index than previously.

"Most of the January indicators reflect growth in activity year on year, except in the mining sector, which didn't top output registered in the same month last year," says today’s report.

Last year, Chile produced 5.25 million tons of the industrial metal, which represented a decrease of 3.2% from what it mined in 2010.

The mining sector has a 52.2% weighting, the manufacturing sector has a 37.9% weighting, while the electricity, natural gas and water utilities sectors hold a 9.9% weighting on the INE's new industrial production index.