A Measure of Stocks' Prices Has Only Done This 3 Times Since the S&P 500's Debut. Here's What Happens Next.

The S&P 500 has been in a bull market, with significant gains driven by AI stocks like Nvidia and Palantir. The Shiller CAPE ratio is at a high level, signaling potential market decline. However, other factors like AI market growth and economic optimism may sustain the momentum.