Capital DailyCapital Daily
Markets · Investing · Business
Capital DailyCapital Daily
Finance

September Is the Stock Market's Worst Month on Record. Here's the 1 Move History Says AI Investors Should Make.

September is historically the poorest-performing month in the stock market.

September Is the Stock Market's Worst Month on Record. Here's the 1 Move History Says AI Investors Should Make.

Published September 3, 2026 · Category: Finance

Overview

September has a reputation problem on Wall Street, and if you own a basket of artificial intelligence (AI) stocks, it is hard to ignore. Investors talk about the September Effect the same way people talk about the first week back at the office after a summer vacation: The pace picks up, patience is thin, and small problems suddenly feel bigger.

Since 1928, the S&P 500 (SNPINDEX: ^GSPC) has posted an average return of -1% in September. The Nasdaq Composite (NASDAQINDEX: ^IXIC) features a similar September decline since its inception in 1971.

Details

The long-running theory behind September sell-offs is that as fund managers come back from vacation, they rebalance their portfolios -- taking gains in stocks that have rallied hard while harvesting losses from laggards.

Continue reading

Source

Originally published at www.fool.com.

Related Articles

CD
Capital Daily Newsroom

Capital Daily covers markets, crypto and commodities for Asia & the Middle East — tier-1 desk research, AI-driven analysis, institutional-grade data. Tip our newsroom: [email protected]

Email the newsroom →
Disclaimer: This article is for informational purposes only and does not constitute investment advice. Data may be delayed up to 15 minutes. Past performance is not indicative of future results. Consult a licensed financial advisor before making investment decisions.