[jfengel]

As a quick-and-dirty measure of corporate profits, the S&P 500 P/E ratio is at 33 and rising. A "good" number is more like 15-20. Historically, the market has crashed whenever the number gets in this range.

It's far from a perfect measure, but it does suggest that the market is untethered from reality. Profits just aren't going up fast enough to justify the increase in stock prices.

A deeper dive would try to untangle some of the more obviously egregious prices, especially in the AI space, where expenses are high and profits are nonexistent.