I am not sure whether your chart is showing the correct data. The mine production of gold is increasing by around 4% to 5% per year, despite the labor issues in South Africa (one of the most important gold producers in the world). Some 2,860 tonnes of gold were mined out in the year 2014, with more than one-sixth of that output occurring in China.
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Thanks for your input: I basically read everywhere that gold mining is becoming very expensive/difficult to extract hence production goes down. Can you please give me the link/source where you found that chart?