Midday report: The Shanghai Composite Index fluctuated widely and fell slightly in half a day, with the "three barrels of oil" creating a historic collective two-day limit.

The three major indices collectively fell in the early trading session. By midday, the Shanghai Composite Index fell by 0.07%, the Shenzhen Component Index fell by 1.05%, the ChiNext Index fell by 0.44%, and the CSI 50 Index fell by 1.67%. The total trading volume in Shanghai, Shenzhen, and Beijing totaled 2.0337 trillion yuan by midday, a decrease of 56.5 billion yuan compared to the previous day. Over 3800 stocks in the entire market fell. In terms of sector themes, oil and gas exploration and services, port and shipping, agriculture and forestry, insurance, coal mining and processing, banking, pork, tourism and hotels, securities, and power sectors saw the biggest gains. Military equipment, semiconductors, diamond cultivation, commercial aerospace, dyes, computing power leasing, brain-machine interfaces, film studios, and non-ferrous metal sectors saw the largest declines. On the market front, news of the closure of the Strait of Hormuz by Iran continued to drive up sectors such as oil and gas, shipping, and others. Chinese oil companies such as PetroChina and CNOOC hit the limit up for the second consecutive trading day. Companies like China Merchants Energy Shipping also hit the limit up. Four departments issued documents to promote the high-quality development of technology insurance, leading to a rise in the insurance sector with companies like Ping An, China Life, and New China Insurance recording gains. Geopolitical conflicts increased risk aversion sentiment, benefiting the banking sector with Chongqing Bank surging by 7% midday. Food, coal, and securities sectors also performed well. On the other hand, the military and non-ferrous metal sectors saw a pullback after failing to continue their upward momentum, with companies like Hana Aerospace, Zhongheng Resources, and China Rare Earth leading the declines. Growth stocks like semiconductor companies also fell due to risk aversion sentiment, with companies like Ficther Energy and GTK Micro leading the way.