The S&P 500 is a benchmark index that many investors treat as a stand-in for the broader stock market. The index now includes nine stocks with a market cap over $1 trillion. The stock market may experience major swings depending on what happens to these nine stocks alone.

Enthusiasm about artificial intelligence has propelled markets to record highs this year. But the fierce ascent has also raised concerns about a bubble.

Tesla stock is trading lower Tuesday afternoon as investors weigh the implications of the company's latest product launches against broader market concerns.

The S&P 500 has been roaring higher, registering gains of 24% and 23%, respectively, over 2023 and 2024, and right now heading for a new double-digit annual increase. The famous benchmark even reached record levels in recent days, reinforcing the strength of the current bull market rally.