0 ppb5 ppb10 ppb15 ppb20 ppb25 ppb30 ppb35 ppb40 ppb45 ppb50 ppb55 ppb60 ppb65 ppb70 ppb75 ppb199019911992199319941995199619971998199920002001200220032004200520062007200820092010201120122013201420152016
China
India
United States
China
India
United States
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