CHART OF THE DAY: The S&P 500's top 7 stocks have soared more than 50% in 2023, while everything else is 'basically flat'

• The S&P 500's top seven stocks have gained more than 50% this year, Apollo's Torsten Sløk wrote.
• But the rest of the benchmark index's stocks have collectively risen about 5%.

Our Chart of the Day comes from Apollo Global Management and demonstrates the widening performance gap between the S&P 500's top seven stocks and all its other listed equities.

While the leading firms have rocketed more than 50% this year, the remaining 493 equities have stayed "basically flat," Apollo Chief Economist Torsten Sløk wrote on Saturday.

Specifically, they've risen about 5% through the year. The overall S&P 500, which is weighted by market cap, is up over 13% for the year.

"The bottom line is that if you buy the S&P 500 today, you are basically buying a handful of companies that make up 34% of the index and have an average P/E ratio around 50," he wrote.

Known as the "Magnificent 7," the massive gains seen by Apple, Meta, Microsoft, Amazon, Nvidia, Google, and Tesla were sparked by hype over artificial intelligence.

On Monday, Amazon said it will invest up to $4 billion in Anthropic, an artificial intelligence company that's considered a rival to ChatGPT creator OpenAI, which counts Microsoft as a top investor.

The AI-led stock rally has acted as a counterweight to equity headwinds this year, whether they be rising interest rates or last spring's banking turmoil.

But the past two months have seen the seven stocks pare some gains after climbing nearly 70% at its mid-July peak. This month, top performer Nvidia was not spared from bearish sentiments, and has lost $180 billion in market capitalization.

That's in part as soaring bond yields now offer a profitable alternative to the equity market, while declining consumer savings and a cooling labor market make further growth uncertain.

But excitement for the cohort still remains among Wall Street observers. Last week, Wedbush Securities noted that the tech sector is estimated to boost spending over the next 12-18 months, helping the rally overcome further headwinds.