On October 9, the market dipped in the afternoon before recovering, with all three major indices turning positive. The ChiNext Index fell more than 3% at one point. By the close, the Shanghai Composite Index rose 0.05%, the Shenzhen Component Index gained 0.17%, and the ChiNext Index added 0.22%. On the board, hot topics rotated rapidly. The film and media sectors continued to climb, the lithium battery concept strengthened during intraday trading, and concepts such as agriculture, major consumption, and organosilicon showed active performance. On the declining side, the wind power equipment sector fluctuated downward, and the PCB concept weakened. More than 3,200 individual stocks across the entire market advanced. The combined turnover of the Shanghai and Shenzhen markets reached 1.9 trillion yuan, an increase of 218.4 billion yuan from the previous trading day.

The parabolic trajectory of a K-line chart shares some similar "laws of motion" with the real world: regardless of the time frame, if affected only by gravity (sellers), the height (price) will decline in one direction. When encountering an obstacle (support level), it may bounce slightly but struggle to exceed the previous high. Only when sufficient and sustained upward thrust (large buying volume) is obtained can the downward trend be temporarily reversed and reach a higher level. Today's A-share market perfectly embodied this change — in the morning session, the market extended yesterday's and the pre-holiday decline, hitting a stage low. The Shanghai Composite Index fell to a minimum of 3,754.14 points, approaching the previous low of 3,741.11 points set on July 20. The dual-innovation indices, Wind All A, and other stock indices were pushed even lower. For example, the ChiNext Index touched a minimum of 2,932 points, marking both a new low for the year and approaching the low from last November.

But after the afternoon session opened, the declines in major stock indices narrowed significantly, and they collectively turned positive after 14:00, forming a long lower shadow — in other words, the commonly called "deep V" pattern had emerged. The variable that brought about the "bottom-fishing synergy" is not unfamiliar to most: it is still "broad-based ETFs collectively surging in volume," corresponding to a wave of large capital entering to support the market. Wind data shows that by the close, the top 20 broad-based ETF products by turnover all saw volume increases compared to the previous trading day, with some products even doubling their turnover. The specific list is as follows. From the broad-based indices involved, it is not difficult to see that the main direction of the support capital (i.e., notable volume increases) was concentrated at both ends: small and mid-cap (CSI 1000, CSI 500) and large-cap blue chips (SSE 50, CSI 300).

However, it must be pointed out that based on experience in recent years, a single-day "deep V" may not be sufficient to reverse a short-term downward trend. From the perspective of ordinary investors, if the capital supporting the market through broad-based ETFs can "buy more" and "buy continuously," the probability of the relevant indices stabilizing and rebounding becomes greater. Taking the ChiNext ETF E Fund (159915) as an example, according to Wind data, since September 2024, after several stage lows in the ChiNext Index appeared, if a continuous rebound rally followed, it typically corresponded to 4-5 trading days of continuous net capital inflow (with relatively large amounts). For instance, in late September 2024 (the starting point of the "924 rally") and around April 7, 2025, as shown in the chart below. Similarly, during the continuous decline in July this year, from July 16 to 20 (3 days) and from July 24 to 30 (5 days), only after two consecutive waves of large capital inflow to support the market did the ChiNext Index usher in a rebound in the first half of August.

Therefore, in the next few trading days (that is, next week), for stock investors deciding to participate in at least one "oversold rebound" rally, the strategy of "advancing and retreating together with large capital" actually has certain value. Finally, returning to sector performance. From the perspective of gains and losses, during the morning bottoming phase, the "optics" and "chips" sectors that led declines yesterday were once again sold off by capital. When the "V-turn" occurred in the afternoon, although these two directions saw some capital return, they still closed lower. In the morning session, the battery sector was the first to receive capital support, which may be related to the unusual movement in CATL, and "King Ning" itself also has expectations of share buybacks. In the afternoon, after the market realized that "support capital had entered," the main sectors that surged included: film and cinema, cultural media, and gaming. On the news front, China's first AI hyper-realistic theatrical film "Sanxingdui: Future Past" has been scheduled to hit theaters nationwide on October 23. Planting and agriculture, retail (major consumption). On the news front, the World Meteorological Organization recently released information predicting that from October to December 2026, sea surface temperatures in the central and eastern tropical Pacific will rise to record levels, with El Niño expected to peak in December. El Niño often brings widespread abnormal climate conditions, disrupting the planting rhythm and output of major grain-producing regions. Global crop supply faces contraction pressure, and the food security theme has once again become a market focus. Diversified finance, securities. On the news front, the Securities Association of China recently circulated within the industry a report on the operating conditions of securities companies for the first half of 2026: 150 securities firms achieved operating revenue of 329.81 billion yuan and net profit of 138.664 billion yuan, representing year-on-year growth of 31.38% and 23.50% respectively. Generally speaking, after the broad rally brought by a "deep V," capital tends to focus on a few stronger, more proactive directions to continue huddling. Therefore, while watching whether the market rebound can continue, investors who have the capacity may also want to track sector rotation and optimize their holdings.