Workflow
期现基差收敛
icon
Search documents
【知识科普】股指期货交割日尾盘拉升是怎么回事?
Sou Hu Cai Jing· 2025-03-29 16:05
Core Viewpoint - The phenomenon of end-of-day price surges on stock index futures settlement days is driven by various market mechanisms and investor behaviors, which need to be understood in a comprehensive manner [1]. Group 1: Settlement Price Mechanism - The settlement price for stock index futures is typically based on the arithmetic average of the underlying index over the last 1-2 hours on the expiration date, such as the last 2-hour average for the CSI 300 index [4]. - Investors may engage in concentrated trading at the end of the day to "manipulate" the settlement price, especially if they believe it will impact their profits or losses from open positions [4]. Group 2: Position Adjustment and Liquidity Changes - On settlement days, there is pressure to close positions as open contracts must be settled in cash at the settlement price, leading some investors to close positions at the end of the day to avoid physical delivery or optimize settlement costs [6]. - As the market approaches closing time, some investors may exit, resulting in reduced liquidity, which can significantly impact prices and create "surge" or "crash" scenarios [6]. Group 3: Arbitrage and Futures-Spot Linkage - As the settlement date approaches, futures prices typically converge towards the spot index, and if futures are trading at a discount, arbitrageurs may buy futures and sell the spot to drive up futures prices and narrow the basis [7]. - Algorithmic trading may trigger automated arbitrage strategies based on basis and volatility indicators at specific times, exacerbating short-term price fluctuations [7]. Group 4: Market Psychology and Expectation Games - Some traders may anticipate fund movements on settlement days (such as institutional rebalancing or retail investor behavior) and position themselves accordingly, influencing end-of-day market activity [8]. - Investors with information advantages, such as knowledge of large clients' positions, may exploit this information at the end of the day for profit [8]. Group 5: Potential Manipulation Risks - Abnormal price fluctuations at the end of the day can raise suspicions of manipulation, particularly if there are efforts to inflate the settlement price in conjunction with spot holdings for profit, which may violate trading regulations [9]. - Regulatory bodies typically increase monitoring of trading activities on settlement days to prevent such manipulative behaviors [9].