2026年3月A股重点指数调样公告解读

• The report introduces a comprehensive impact coefficient model to measure the influence of index rebalancing on individual stocks, particularly focusing on the March 2026 adjustments for key indices such as STAR 50, STAR-ChiNext 50, STAR 100, Dividend Low Volatility 100, and Beijing Stock Exchange 50[9][11][14] - The comprehensive impact coefficient is defined as follows: $ effect_total_{s}=\sum_{i=1}^{n}\frac{wt_chg_{s_{i}}\times fund_size_{i}}{amount_avg_{s_{i}}20} $ where: - $ wt_chg_{s_{i}} $ represents the weight change of stock $ s $ in index $ i $ - $ fund_size_{i} $ is the tracking scale of index $ i $ - $ amount_avg_{s_{i}}20 $ is the average trading volume of stock $ s $ over the past 20 days[11] - The model evaluates the impact of passive trading caused by index rebalancing, emphasizing that larger indices with higher tracking scales (e.g., STAR 50 with 1489 billion RMB) generate more significant passive trading effects, creating potential investment opportunities for stocks added to these indices[13][14] - The report provides detailed calculations of the comprehensive impact coefficients for stocks with significant adjustments, identifying stocks like Jikang Technology (impact coefficient: 5.95), Zhongke Feice (impact coefficient: 1.73), and Taoli Bread (impact coefficient: 1.55) as having notable positive impacts due to their inclusion in indices such as Beijing Stock Exchange 50 and STAR 50[14][17] - Stocks removed from indices also exhibit negative impact coefficients, such as Weida Optoelectronics (-2.95), Jike Shares (-2.65), and Junshi Biosciences (-1.73), reflecting the adverse effects of exclusion from key indices[17]