沪深300能源指数下跌0.82%，前十大权重包含中海油服等

Core Viewpoint - The Shanghai Composite Index opened lower but rose later, while the CSI 300 Energy Index fell by 0.82% to 2106.64 points, with a trading volume of 4.239 billion yuan. The CSI 300 Energy Index has decreased by 0.31% over the past month, 5.24% over the past three months, and 13.23% year-to-date [1]. Group 1: Index Performance - The CSI 300 Energy Index has shown a decline of 0.31% in the last month, 5.24% in the last three months, and 13.23% year-to-date [1]. - The top ten holdings in the CSI 300 Energy Index include China Shenhua (25.01%), China Petroleum (17.54%), and China Petrochemical (16.09%) [1]. Group 2: Market Composition - The CSI 300 Energy Index is composed of 96.30% from the Shanghai Stock Exchange and 3.70% from the Shenzhen Stock Exchange [2]. - The industry composition of the CSI 300 Energy Index includes coal (50.97%), integrated oil and gas companies (33.62%), and fuel refining (10.16%) [2]. Group 3: Index Adjustment Mechanism - The index samples are adjusted biannually, with adjustments occurring on the next trading day after the second Friday of June and December [2]. - Weight factors are generally fixed until the next scheduled adjustment, with temporary adjustments made in response to changes in the CSI 300 Index samples [2].