In Reply to: Re: (link) Date Center debts, Deja Vu all over again? posted by TheHappyBurgermeister on October 17, 2026 at 16:21:51
He's correct.
The 10 largest companies in the S&P 500, most of which are heavily dependent on AI except for Apple, account for roughly 50% of the index.
When you invest in an S&P 500 index fund, your money is weighted by each company's market capitalization. That means you're investing far more heavily in those 10 companies than in the other 490 combined. This creates significant concentration risk, particularly when so much of the index's performance depends on the AI industry.