The "Magnificent Seven" stocks (Apple, Amazon, Alphabet, Meta, Microsoft, Nvidia, and Tesla) were collectively up >60% last year and are now 30% of the entire S&P500. They are all heavily invested in AI products.
I just checked the first two, Apple and Amazon, and they're trading 28% and 23% higher than they were 3 years ago. Annualized returns from the SP 500 have been a little over 10%. Some of that comes from dividends, but Apple and Amazon give out extremely little in the way of dividends.
I'm not going to check all of the companies, but at least looking at the first two, I'm not really seeing anything out of the ordinary.
