(Bloomberg) -- Gold output in South Africa, once the world’s biggest producer of the metal, declined the most since February 2017 in May.

Production dropped 16.2 percent from a year earlier, compared with a revised 5.8 percent contraction in April, Pretoria-based Statistics South Africa said Thursday in a statement on its website. That’s an eighth straight month of decreases.

Total mining output shrank for a third month, dropping 2.6 percent from a year earlier compared with a revised 4.4 percent retreat in April, it said. Production of platinum-group metals, of which South Africa has the largest known reserves, increased for the first time in six months, expanding 9.6 percent from a revised 6.3 percent contraction a month earlier.

Aging infrastructure, reserve depletion and accidents have raised costs and curbed mines’ output in South Africa. Mining companies came under added pressure late last year and in the start of 2018 from the stronger rand and have responded by closing shafts and cutting thousands of jobs in a labor-intensive industry.

To contact the reporter on this story: Ana Monteiro in Johannesburg at amonteiro4@bloomberg.net

To contact the editors responsible for this story: Rene Vollgraaff at rvollgraaff@bloomberg.net, Gordon Bell

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