股市风险偏好回落，股指震荡下跌

1. Report Industry Investment Rating - No relevant content provided 2. Core Viewpoints of the Report - On September 4, 2025, all stock indices showed weak oscillations and significant declines. The total trading volume of the Shanghai, Shenzhen, and Beijing stock markets was 2581.9 billion yuan, an increase of 186.2 billion yuan from the previous day, and nearly 3000 stocks declined. Due to the significant gains of some stocks, the profit - taking demand of profit - making funds increased, leading to a short - term technical adjustment in the stock indices, with the CSI 500 and CSI 1000 indices being more affected. However, in the medium - to - long term, the positive policy expectations and loose capital situation strongly support the stock indices, and the logic of their upward movement remains strong. Recently, the joint working group of the Ministry of Finance and the People's Bank of China held its second group leader meeting, indicating a clear expectation of policy support for the economy. The liquidity is relatively loose, and in the context of the "asset shortage", the attractiveness of equity assets is strong, with incremental funds continuously flowing in, which will drive the repair of stock valuations. In general, due to the increased profit - taking demand of profit - making funds, the stock indices are expected to fluctuate widely in the short term. Currently, the implied volatility of options continues to rise. Considering the medium - to - long - term upward trend of the stock indices, one can continue to hold bull spreads or ratio spreads for a mild bullish view [3]. 3. Summary by Related Catalogs 3.1 Option Indicators - On September 4, 2025, the 50ETF fell 1.72% to 3.034; the 300ETF (Shanghai Stock Exchange) fell 2.04% to 4.456; the 300ETF (Shenzhen Stock Exchange) fell 2.11% to 4.593; the CSI 300 Index fell 2.12% to 4365.21; the CSI 1000 Index fell 2.30% to 7041.15; the 500ETF (Shanghai Stock Exchange) fell 2.32% to 6.779; the 500ETF (Shenzhen Stock Exchange) fell 2.62% to 2.710; the GEM ETF fell 4.15% to 2.751; the Shenzhen 100ETF fell 2.54% to 3.226; the SSE 50 Index fell 1.71% to 2910.47; the STAR 50ETF fell 6.08% to 1.28; and the E Fund STAR 50ETF fell 6.22% to 1.25 [5]. - The trading volume PCR and position PCR of various ETF options and index options changed compared to the previous trading day. For example, the trading volume PCR of SSE 50ETF options was 94.23 (75.73 the previous day), and the position PCR was 81.16 (87.40 the previous day) [6]. - The implied volatility of at - the - money options in September 2025 and the 30 - trading - day historical volatility of the underlying assets of various options were reported. For instance, the implied volatility of at - the - money options of SSE 50ETF options in September 2025 was 19.16%, and the 30 - trading - day historical volatility of the underlying asset was 14.44% [7]. 3.2 Related Charts - The report provides a series of charts for different types of options, including the trends, volatility, trading volume PCR, position PCR, implied volatility curves, and at - the - money implied volatility of different terms of various ETF options and index options such as SSE 50ETF options, SSE 300ETF options, etc. [9][19][32]