Aluminium Corp.of China Ltd(Chinalco), the listed unit of China’s biggest maker of the lightweight metal, slid 0.6 percent to 6.57 yuan. Shenyin & Wanguo Securities Co. lowered Chinalco’s earnings per-share forecast for this year by 38 percent to 0.05 yuan and for 2012 by 18 percent to 0.18 yuan, citing capacity expansion and rising costs from increases in power rates, Ye Peipei, Guo Peng and Xu Ruoxu, analysts at the Shanghai-based brokerage, said in a report yeaterday.