分析：AI相關股票10月重挫，考驗美股大盤韌性

路易斯・克勞斯科普夫（Lewis Krauskopf）報導By Lewis Krauskopf

紐約，11月2日（路透）—— 美國AI與科技股價格大幅下跌，正在考驗投資人轉向其他股票領域的熱情；這種輪動近幾週支撐了大盤指數。NEW YORK, Nov 2 (Reuters) - A steep decline in the prices of US AI and technology stocks is testing investors' enthusiasm to shift into other equity areas, a rotation that has propped up broader indexes in recent weeks.

Alphabet（Alphabet）、亞馬遜（Amazon）與英特爾（Intel）令人失望的業績，對AI交易造成最新打擊。投資人擔心，要支應龐大的投資支出，需要巨額資金。他們也開始質疑，投資報酬是否能強勁到足以合理化這些支出。Disappointing results from Alphabet, Amazon and Intel dealt the latest blow to the AI trade. Investors worry about the hefty financing needed to fund massive investment spending. They are also starting to question whether returns will be robust enough to justify that spending.

10月大盤表現遠優於科技股與AI相關股票，但若規模龐大的AI交易出現更嚴重回檔，大盤未必能承受。光是科技類股在標普500指數中的權重就達38%。The broader market in October held up far better than tech- and AI-exposed equities did, but it may not be able to endure a more severe pullback in the massive AI trade. The tech sector alone accounts for a 38% weight in the S&P 500.

投資人警惕賣壓擴散的跡象。主要警訊將是，AI超大規模雲端服務業者大幅縮減支出計畫的跡象。它們對資料中心及其他基礎設施的投資，一直是整體經濟成長的關鍵動力。Investors are wary of signs that the selling will spread. A main alarm would be indications that the AI hyperscalers pull back significantly on spending plans. Their investment in data centers and other infrastructure has been a key driver for overall economic growth.

Nationwide首席市場策略師馬克・哈克特（Mark Hackett）表示：「你可以出現一個月領漲族群明顯轉換、科技股走弱，而其他所有類股相對強勢。」不過，「如果再出現一個月（大幅）下跌……它規模太大，從數學上來說很困難，但我認為更重要的是，從心理層面來說也很困難。」"You can have a month of a significant shift in leadership and tech weakness and relative strength in everything else," said Mark Hackett, chief market strategist for Nationwide. However, "if you have another month of (a steep) drop … it's so big that mathematically it's difficult, but I think even more importantly, psychologically it's difficult."

週五的走勢凸顯了這類憂慮。科技類股當天重挫4.2%，其中英特爾暴跌近29%，拖累標普500指數下跌1.8%。Friday's action illustrated such worries. A whopping 4.2% drop on the day for the tech sector, which included a nearly 29% tumble for Intel, drove a 1.8% decline for the S&P 500.

10月，標普500科技類股下滑6.8%，創2025年3月以來最大單月跌幅。然而，標普500指數11大類股中有9個在10月上漲，使該基準指數最終單月跌幅不到1%。For October, the S&P 500 tech sector slid 6.8%, its biggest monthly drop since March 2025. Yet nine of the S&P 500's 11 sectors gained in October — allowing the benchmark index to end with a monthly decline of less than 1%.

AI與其他所有領域之間的輪動ROTATIONS BETWEEN AI AND EVERYTHING ELSE

2026年迄今，標普500指數上漲逾10%。然而，輪動一直是過去一年的主題。領漲族群經常在重量級科技與AI股一方，以及範圍更廣的一組類股另一方之間擺盪。The S&P 500 is up more than 10% so far in 2026. Yet rotations have been a theme for the past year. Leadership has often vacillated between heavyweight tech and AI stocks on one hand, and a broader group of sectors on the other.

舉例來說，9月呈現與10月相反的趨勢，當月由科技與AI股主導。September, for example, showed opposite trends to October, with dominance that month from tech and AI stocks.

哈克特說：「今年在指數層面穩定得令人難以置信。但表面之下波動非常大。」"This year has been unbelievably stable at the index level," Hackett said. "But there's so much volatility beneath the surface."

10月交易顯示市場有擴大的跡象。儘管AI相關個股大幅下跌，標普500指數成分股中超過70%當月仍上漲。代表小型股與中型股的指數10月也上漲。October trading indicated a sign of broadening. Despite sharp declines in AI names, more than 70% of S&P 500 constituents were up on the month. Indexes representing small- and mid-cap stocks also rose in October.

愛德華瓊斯（Edward Jones）資深全球投資策略師安傑洛・庫爾卡法斯（Angelo Kourkafas）表示：「企業與消費者基本面仍然健康。在這樣的背景下，投資人希望維持股票曝險。但現在他們想降低AI集中風險，並加碼能提供不同報酬來源的領域。」"Both corporate and consumer fundamentals remain healthy," said Angelo Kourkafas, senior global investment strategist at Edward Jones. "In this backdrop, investors want to maintain equity exposure. But now they want to reduce AI concentration risk and are adding to areas that offer differentiated sources of return."

AI支出成為關注焦點，以判斷是否波及更廣層面AI SPENDING IN FOCUS FOR BROADER FALLOUT

如果AI題材更嚴重失速，這種維持股票曝險的意願短期內可能面臨挑戰。That desire to maintain equity exposure could be challenged in the near term, if the AI theme falters more severely.

AI投資支出不僅帶動半導體及參與興建資料中心的公司獲利，也一直是美國整體經濟成長的核心。AI investment spending has not only driven profits for semiconductors and companies involved in building data centers, it has also been central to overall US economic growth.

庫爾卡法斯說，如果大型科技公司「開始削減資本支出，而這些支出支撐了經濟成長、推升了經濟許多不同領域的獲利，那就可能更有影響力，足以帶動更廣泛的避險情緒」。If big tech companies "start pulling back on capex, which has supported economic growth, it has boosted earnings across many different areas of the economy — that can be something that may be more impactful in terms of driving a broader risk-off sentiment," Kourkafas said.

牛津經濟研究院（Oxford Economics）估計，近期美國經濟成長約有三分之一來自AI。這包括支持AI基礎設施擴張的直接投資所產生的淨影響，以及股市上漲帶來的財富效果對消費支出的部分貢獻。Oxford Economics estimates that about one-third of recent US economic growth stems from AI. That includes the net impact of direct investment to support expansion of AI infrastructure as well as some contribution from the wealth effect from stock market gains that has lifted consumer spending.

退休與財富服務提供商Empower首席投資策略師瑪塔・諾頓（Marta Norton）表示：「消費者狀況沒問題，但消費者不是經濟看起來良好的原因。經濟看起來良好，是因為AI。所以，如果你開始真正以有意義的方式抽走AI的支撐，我認為那會改變市場的動態。」"The consumer is fine, but the consumer isn't the reason the economy looks good. The economy looks good because of AI," said Marta Norton, chief investment strategist at retirement and wealth services provider Empower. "So you start pulling the rug out from under AI in an actual meaningful way, I think that changes the dynamics for the markets."

與此同時，市場走勢可能開始引發更廣泛擔憂。標普500指數週五收在100日移動平均線這條中期趨勢線之下，為4月以來首見。Meanwhile, the market action could start to cause broader worry. The S&P 500 on Friday closed below its 100-day moving average — a medium-term trendline — for the first time since April.

米勒塔巴克（Miller Tabak）首席市場策略師馬修・梅利（Matthew Maley）表示，雖然該指數過去兩年曾數度從這條趨勢線反彈，但「每當它以任何實質方式跌破……接下來幾週都會出現更大幅度下跌」。While the index has bounced off that trendline several times in the past two years, "when it has broken below … in any material way, it was followed by a much further drop over the following weeks," said Matthew Maley, chief market strategist at Miller Tabak.

梅利在週五的一份報告中表示：「如果主要股指開始以更具說服力的方式下跌，投資人很可能會停止輪動到其他類股……轉而輪動到現金。」"If the major averages begin to drop in a more compelling manner, it is very likely that investors will stop rotating into other sectors … and start rotating into cash," Maley said in a note on Friday.

（路易斯・克勞斯科普夫報導；梅根・戴維斯（Megan Davies）與大衛・葛瑞格里奧（David Gregorio）編輯）(Reporting by Lewis Krauskopf; Editing by Megan Davies and David Gregorio)