Core Viewpoint - The article argues that the notion of "stock index futures settlement day must decline" is a baseless myth in the capital market, akin to historical witch hunts, aimed at misleading retail investors into selling their stocks prematurely [1][3][5]. Group 1: Market Analysis - Historical data from the S&P 500 index shows that on "Quadruple Witching Days," the index has risen 65% of the time over the past 30 years, with an average fluctuation of only 0.23%, contradicting the idea of a "must decline" phenomenon [7]. - In the A-share market, from 2015 to 2025, the Shanghai Composite Index rose on 58 out of 120 settlement days, with an average fluctuation of ±0.52%, indicating no significant downward trend [7][9]. - The probability of the CSI 300 index rising on settlement days is only 46%, with extreme fluctuations exceeding 2% occurring only 5 times, representing 4.2% of the total [7]. Group 2: Market Mechanisms - The trading volume of stock index futures on settlement days is minimal compared to the total market capitalization of 106 trillion yuan, making it unlikely to significantly impact the market [9][11]. - The settlement price for A-share stock index futures is based on the arithmetic average of the last two hours of the cash index, making manipulation nearly impossible due to the required capital and regulatory oversight [11][13]. - The monthly settlement system in the A-share market is designed to avoid conflicts with major financial reports and macroeconomic data releases, which is a strategic choice rather than a disadvantage [11][13]. Group 3: Investor Behavior - A survey by the China Financial Futures Exchange in 2024 indicated that over 70% of investors support maintaining the current settlement model, with less than 7% advocating for a shift to quarterly settlements [13]. - The article emphasizes that the so-called "witch hunt" in the capital market exploits retail investors' fears, leading them to make irrational decisions based on misinformation [15].