The stock market has been roaring for the past decade, with the S&P 500 (^GSPC) boasting an annualized return of 13%.

On Friday, Goldman Sachs (GS) published a research note projecting the next decade won’t be as friendly to investors in the benchmark index. The S&P 500 will deliver an annualized return of 3% over the next 10 years, Goldman projected, noting that more than a third of the index being concentrated in just 10 stocks has typically led to below-average returns.

But Goldman Sachs equity strategist Ben Snider told Yahoo Finance the headline projection isn’t as bearish as it may seem, nor is it a call to get out of stocks now.

“We remain very confident in the long-term outlook for US economic growth,” Snider said in an interview on Tuesday. “We remain very confident in the outlook for long-term corporate profit growth. We feel good about the long-term outlook for the average [S&P 500] stock. The concern that we have is that concentration is extremely high … And when we put that in our models, it points to low average returns.”

Right now, the 10 largest stocks in the S&P 500 represent more than a third of the index, putting market concentration near its highest level in 100 years, per Goldman. Using history as a guide, this has typically led to below-average returns for the following decade, Snider said.

This would likely happen through stocks that make up that large concentration in the index — like Nvidia (NVDA), Apple (AAPL), or Microsoft (MSFT) — falling off. And just as the “Magnificent Seven” tech stocks helped lead the market higher, in this scenario they’d lead the market lower.

“The idea here is you have a few stocks that have an unusually large representation of market cap,” Snider said. “And if their weight goes back to some kind of normal, that would weigh on the aggregate index as well.”

There isn’t a shock clearly in view that Goldman believes starts the decade of bad returns. That’s why the team sees the S&P 500 hitting 6,300 in the next 12 months. The issue for Goldman in its most recent exercise is that a decade is a long time.

“The longer your investment horizon, the more uncertain all the catalysts that will take place during that horizon,” Snider said. “And so just given the starting point of the concentration, history would tell us there is likely to be some catalyst over the next decade that causes that to revert.”

But he noted the caveat that the unwinding of market concentration “doesn’t need to happen within the next 10 years, and it doesn’t necessarily need to weigh on the equity market, because there could be dramatic strength from the rest of the equity constituents.”

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Some on Wall Street don’t see that unwind happening anytime soon. DataTrek co-founder Nicholas Colas wrote in a note to clients Tuesday morning that 3% annualized returns or worse “only come when something very, very bad has occurred.”

The issue at hand is how long the current exceptionalism in the market, particularly in US tech giants, can last.

“The bottom line is that we believe the next decade will see S&P returns at least as strong as the long run average of 10.6 percent, and possibly better,” Colas wrote after detailing how continued gains in disruptive tech led by US companies could fuel the gains.

During a reporter roundtable on Monday, JPMorgan Asset and Wealth Management laid out an optimistic case for stocks over the next 10 years. But when asked about Goldman’s call for a 3% average annual return over the next decade, JPMorgan Wealth Management’s global head of multi-asset and portfolio solutions, Monica Issar, admitted Goldman’s team makes a fair point on the recent run-up in stocks, while adding the outlook for stocks still remains relatively strong.

“We are at higher starting points,” Issar said. “So we don’t want to shy away from that conversation. We want to make sure that people do understand that we are assuming [stock] multiple contractions.

“We’re just saying that that multiple contraction will be offset with healthier macro fundamentals over the next 10 years, with healthier corporate fundamentals over the next 10 years, and that foundation is a sturdier point in time for investors to allocate capital.”

Issaar’s point gets to the crux of what Snider says long-term-minded investors have been telling him after reading the report.

“It’s not that [investors are] bearish on equities,” Snider said. “In fact, they still are going to own US equities, but they’re just preparing themselves for lower returns over the next decade than the last decade.”

Snider added about his team’s view, “We are still very optimistic about the US equity market.”

Josh Schafer is a reporter for Yahoo Finance. Follow him on X @_joshschafer.

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