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1. Report Industry Investment Rating - Not provided in the report 2. Core Viewpoint of the Report - For stock index options, with the upward movement and decreasing volatility, it is advisable to consider constructing a bull call spread strategy when implied volatility is at a low level [2] 3. Summary According to Relevant Catalogs 3.1 Option Market Data Statistics - Underlying Market Statistics: The closing prices of the Shanghai - Shenzhen 300 Index, CSI 1000 Index, etc. showed increases. For example, the Shanghai - Shenzhen 300 Index closed at 4621.75, up 37.22 points, with a trading volume of 199.62 billion hands, an increase of 2.82 billion hands. The CSI 1000 Index closed at 7423.05, up 80.55 points, with a trading volume of 240.92 billion hands, an increase of 25.19 billion hands. Some ETFs also had price increases, such as the Shanghai - Shenzhen 300 ETF (Huatai - Bairui) which closed at 4.732, up 0.034 [3] - Option Market Statistics: The trading volume of some options increased, like the Shanghai - Shenzhen 300 Index option with a trading volume of 139193, an increase of 13838, and an open interest of 188259, an increase of 3838. The VL - PCR and OI - PCR of different options varied, for instance, the VL - PCR of the Shanghai - Shenzhen 300 Index option was 62.29% and the OI - PCR was 80.47% [3] 3.2 Option Volatility Statistics - Near - month Options: The ATM - IV of different options had different changes. For example, the ATM - IV of the Shanghai - Shenzhen 300 Index option was 11.94%, a decrease of 0.23%, and its 10 - day HV was 9.02%, a decrease of 0.26% [6] - Next - month Options: The ATM - IV of the Shanghai - Shenzhen 300 Index option in the next - month was 14.85%, an increase of 0.50%, and its 10 - day HV was 14.26%, an increase of 0.11% [6] 3.3 Option Index Data Statistics - Not provided in the report 3.4 Analysis of Different Option Types - For each type of option (e.g., Shanghai 50 Index option, Shanghai - Shenzhen 300 Index option, etc.), there are corresponding analysis charts including full - contract PCR, main - contract skewness trend, volatility cone, and volatility term structure [10][14]